liu.seSök publikationer i DiVA
Ändra sökning
Avgränsa sökresultatet
101112131415 601 - 650 av 720
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 601.
    Wigenius, Jens A.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Persson, Gustav
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Nilsson, Peter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Organisk Kemi. Linköpings universitet, Tekniska högskolan.
    Widengren, Jerker
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Dark states in oligothiophenes: evidence from fluorescence correlation spectroscopy and dynamic light scatteringManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    We report studies of the conjugated pentameric oligothiophene derivative p-FTAA, which changes optical properties in aqueous buffers of varying pH and concentration. Using dynamic light scattering, luminescence spectroscopy and fluorescence correlation spectroscopy, we find evidence for the formation of large clusters of p-FTAA in aqueous environment, formation of very large non-emissive clusters, and the presence of at least two dark transient states, one presumably being a triplet state. The clustering of p-FTAA is therefore an important mechanism. This work provides an interpretation of fluorescence spectra used for the detection of misfolding proteins through interaction with p-FTAA.

  • 602.
    Wigenius, Jens A.
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Persson, Gustav
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Widengren, Jerker
    Experimental Biomolecular Physics, Department of Applied Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Interactions between a luminescent conjugated oligoelectrolyte and insulin during early phases of amyloid formation2011Ingår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 11, nr 8, s. 1120-1127Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Folding of an amino acid polypeptide chain into its native three-dimensional protein is a delicate process. Misfolding may cause assembly of dysfunctional proteins leading to aggregated assemblies, in medicine denoted amyloids, causing Alzheimer’s, Parkinson and a number of other protein related diseases. Amyloids have also shown promising results as building blocks in organic electronic applications, associated to conjugated polymers. Luminescent conjugated oligo- and polythiophenes (LCPs) have been further developed for biosensor applications exhibiting good ability to discriminate and determine different types of amyloid enrichment in complex environments, such as in tissue sections. The nature of interaction between the amyloid assemblies and LCPs is still not fully understood. In this study we use steady-state fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy and fluorescence correlation spectroscopy to follow the interplay between the anionic oligothiophene derivative 4',3'''-Bis-carboxymethyl-[2,2';5',2'';5'',2''';5''',2'''']quinque thiophene-5,5''''-dicarboxylic acid (p-FTAA), and prefibrillar protein assemblies present during the earlier stage of in vitro fibrillation of bovine insulin. Our findings confirm that p-FTAA interacts with pre-fibrillar species of insulin preceding the formation of mature insulin amyloid fibrils, and insights regarding the molecular interplay between p-FTAA and these species are provided.

  • 603.
    Wigenius, Jens
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Björk, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hamedi, Mahiar
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Aili, Daniel
    Department of Materials, Imperial College London, SW7 2AZ London, UK.
    Supramolecular Assembly of Designed α-Helical Polypeptide-Based Nanostructures and Luminescent Conjugated Polyelectrolytes2010Ingår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 10, nr 8, s. 836-841Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Designed polypeptides with controllable folding properties are utilized as supramolecular templates for fabrication of ordered nanoscale molecular and fibrous assemblies of luminescent conjugated polymers (LCPs). The properties of the LCPs as well as the three dimensional conformation of the polypeptide-scaffold determine how the polymers are arranged in the supramolecular construct, which highly affects the properties of the hybrid material. The ability to control the polypeptide conformation and assembly into fibers provide a promising route for tuning the optical properties of LCPs and for fabrication of complex functional supramolecules with well defined structural properties.

  • 604.
    Wigenius, Jens
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Fransson, Sophia
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Conjugated Polyelectrolytes as Reporter Molecules2007Ingår i: E-MRS 2007 Strasbourg,2007, 2007Konferensbidrag (Refereegranskat)
  • 605.
    Wigenius, Jens
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Fransson, Sophia
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Conjugated Polyelectrolytes as Reporter Molecules;Biochip Constructed by Soft Litography Method2007Ingår i: BIOSCOPE 2007,2007, 2007Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

       

  • 606.
    Wigenius, Jens
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Fransson, Sophia
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    von Post, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Inganäs , Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Protein biochips patterned by microcontact printing or by adsorption-soft lithography in two modes2008Ingår i: BIOINTERPHASES, ISSN 1559-4106 , Vol. 3, nr 3, s. 75-82Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Patterning of proteins is critical to protein biochips. Printing of layers of proteins is well established, as is adsorption of proteins to surfaces properly modified with surface chemical functionalities. The authors show that simple methods based on soft lithography stamps can be used to prepare functional antibody chips through both these routes. Both methods incorporate transfer of the stamp material poly (dimethylsiloxane) (PDMS) to the biochip, whether intended or not intended. The results indicate that microcontact printing of proteins always includes PDMS transfer, thereby creating a possibility of unspecific adsorption to a hydrophobic domain.

  • 607.
    Wigenius, Jens
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hamedi, Mahiar
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Limits to Nanopatterning of Fluids on Surfaces in Soft Lithography2008Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 18, nr 17, s. 2563-2571Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Soft lithographic microcontact printing using the residual polydimethylsiloxane (PDMS) found in elastomeric PDMS stamps is demonstrated to lead to unstable prints with sub-micrometer dimensions. The statics and dynamics of the process have been followed with time-resolved atomic force microscopy, imaging ellipsometry, water contact angle measurement, and optical diffraction. It is proposed that this instability places a fundamental limitation on patterning by macromolecular fluids, which is of general relevance to soft lithography and nanoimprint lithography with low viscosity polymers.

  • 608.
    Wigenius, Jens
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Limits to Nanopatterning of Fluids on Surfaces2007Ingår i: E-MRS Strasbourg 2007,2007, 2007Konferensbidrag (Övrigt vetenskapligt)
  • 609.
    Wigenius, Jens
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Magnusson, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Björk, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Andersson, Olof
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    DNA Chips with Conjugated Polyelectrolytes in Resonance Energy Transfer Mode2010Ingår i: LANGMUIR, ISSN 0743-7463, Vol. 26, nr 5, s. 3753-3759Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We show how to use well-defined conjugated polyelectrolytes (CPEs) combined With Surface energy patterning to Fabricate DNA Chips utilizing A fluorescence signal amplification. Cholesterol-modified DNA strands in complex with it CPE are adsorbed to a surface energy pattern, formed by printing with soft elastomer stamps. Hybridization of the surface bound DNA strands with it short complementary strand from Solution is monitored using both fluorescence microscopy and imaging surface plasmon resonance. The CPEs act as antennas, enhancing resonance energy transfer to the dye-labeled DNA when complementary hybridization of the double strand occurs.

  • 610. Wirehn, J.
    et al.
    Carlsson, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biokemi.
    Herland, Anna
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Persson, E.
    Haemostasis Biochemistry, Novo Nordisk A/S, Novo Nordisk Park, 2760 Måløv, Denmark.
    Carlsson, Uno
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biokemi.
    Svensson, Magdalena
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biokemi.
    Hammarström, Per
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biokemi.
    Activity, folding, misfolding, and aggregation in vitro of the naturally occurring human tissue factor mutant R200W2005Ingår i: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 44, nr 18, s. 6755-6763Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tissue factor (TF), a small transmembrane receptor, binds factor VIIa (FVIIa), and the formed complex initiates blood coagulation by proteolytic activation of substrate factors IX and X. A naturally occurring mutation in the human TF gene was recently reported, where a single-base substitution results in an R200W mutation in the TF extracellular domain [Zawadzki, C., Preudhomme, C., Gavériaux, V., Amouyel, P., and Jude, B. (2002) Thromb. Haemost. 87, 540-541]. This mutation appears to be associated with low monocyte TF expression and may protect against thrombosis but has not been associated with any pathological condition, and individuals who present the heterozygous trait appear healthy. Here, we report the activity, folding, and aggregation behavior of the R200W mutant of the 219-residue soluble extracellular domain of TF (sTFR200W) compared to that of the wild-type protein (sTF wt). No differences in stability or FVIIa cofactor activity but an impaired ability to promote FX activation at physiological conditions between the sTFR200W mutant and sTFwt were evident. Increased binding of 1-anilino-8-naphthalene-sulfonic acid (ANS) to sTFR200W indicated a population of partially folded intermediates during denaturation. sTFR200W showed a dramatically increased propensity for aggregate formation compared to sTFwt at mildly acidic pHs, with an increased rate of aggregation during conditions, promoting the intermediate state. The lowered pH resistance could explain the loss of sTFR200W in vivo because of aggregation of the mutant. The intrinsic structure of the sTF aggregates appears reminiscent of amyloid fibrils, as revealed by thioflavin T fluorescence, atomic force microscopy, and transmission electron microscopy. We conclude that the lowered activity for FX activation and the propensity of the mutant protein to misfold and aggregate will both contribute to decreased coagulation activity in TFR200W carriers, which could protect from thrombotic disease. © 2005 American Chemical Society.

  • 611.
    Xia, Yuxin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Polymer/polymer blends in organic photovoltaic and photodiode devices2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Organic photovoltaics devices (OPV) have attracted attentions of scientist for their potential as inexpensive, lightweight, flexible and suitable for roll-to-roll production. In recent years, considerable attention has been focused on new acceptor materials, either polymeric or small molecules, to replace the once dominating fullerene derivatives. The emergence of numerous new non-fullerene materials has driven power conversion efficiency (PCE) up to 17%, attracting more and more interests of commercialization.

    Polymer acceptors with more morphology stability, more absorption and more desired energy levels has been intensively studied and show great potential for large area and low-cost production in the future. OPV at this moment is not yet competitive with inorganic solar cells in PCE but is more attractive in flexibility, low weight and semitransparency. In this thesis, some basic knowledges of OPV is introduced in the first few chapters, while the next chapters are focusing on polymer-polymer blends and investigating novel structures and techniques for large scale production of solar cells and photodetectors aiming at maximizing these advantages to compete with inorganic counterpart.

    Thermal annealing effects on polymer-polymer solar cells based is studied. Annealed devices show doubled power conversion efficiency compared to non-annealed devices. Based on the morphology—mobility examination, we conclude that the better charge transport is achieved by higher order and better interconnected networks of the bulk heterojunction in the annealed active layers. The annealing improves charge transport and extends the conjugation length of the polymers, which do help charge generation and meanwhile reduce recombination. The blend of an amorphous polymer and a semi-crystalline polymer can thus be modified by thermal annealing to double the power conversion efficiency.

    A novel concept of all-polymer organic photovoltaics device is demonstrated in this thesis where all the layers are made out of polymers. We use PEDOT:PSS as semitransparent anode and polyethyleneimine modified PEDOT:PSS as semitransparent cathode, both of which are slot-die printed on polyethylene terephthalate(PET). Active layers are deposited on cathode and anode surfaces by spin coating separately. These layers are then joined through a roll-to-roll compatible lamination process. This forms a semitransparent and flexible solar cell. By laminating a thin layer acceptor polymer to a thick polymer-polymer blend, we can further improve the performance by reducing traps comparing to laminating blend to blend.

    Flexible and semitransparent all-polymer photodiodes with different geometries can be fabricated through lamination. By choosing high band gap polymers and appropriate combination of two or more polymers, organic photodiode with low noise and high specific detectivity can be obtained. Comparison between bilayer and bulk heterojunction devices gives better understanding of the origin of noise and provides ways to improve the performance of photodiodes as detector.

    Noise level is a critical parameter for photodetectors. The difficulties of measuring the noise of photodetectors make some researchers prefer the estimated shot noise as the dominating one and ignore the thermal noise and 1/f noise. The latter two terms are sometimes several orders higher than the former, noting the importance of experimentally measuring noise.

    The use of semi-transparent photovoltaic devices causes an inevitable loss of photocurrent, as light transmitted has not been absorbed. This trivial effect also leads to a loss of photovoltage, an effect partially due to the lower photocurrent but also due to the geometry of the semitransparent photovoltaic device. We here demonstrate and evaluate this photovoltage loss in semi-transparent organic photovoltaic devices, compared with non-transparent solar cells of the same material. Semi-transparent solar cells in addition introduce photovoltage loss when formed by lamination. We document and analyze these effects for a number of polymer blends in the form of bulk heterojunctions.

    Delarbeten
    1. Inverted all-polymer solar cells based on a quinoxaline-thiophene/naphthalene-diimide polymer blend improved by annealing
    Öppna denna publikation i ny flik eller fönster >>Inverted all-polymer solar cells based on a quinoxaline-thiophene/naphthalene-diimide polymer blend improved by annealing
    Visa övriga...
    2016 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 10, s. 3835-3843Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    We have investigated the effect of thermal annealing on the photovoltaic parameters of all-polymer solar cells based on a quinoxaline-thiophene donor polymer (TQ1) and a naphthalene diimide acceptor polymer (N2200). The annealed devices show a doubled power conversion efficiency compared to nonannealed devices, due to the higher short-circuit current (J(sc)) and fill factor (FF), but with a lower open circuit voltage (V-oc). On the basis of the morphology-mobility examination by several scanning force microscopy techniques, and by grazing-incidence wide-angle X-ray scattering, we conclude that better charge transport is achieved by higher order and better interconnected networks of the bulk heterojunction in the annealed active layers. The annealing improves charge transport and extends the conjugation length of the polymers, which do help in charge generation and meanwhile reduce recombination. Photoluminescence, electroluminescence, and light intensity dependence measurements reveal how this morphological change affects charge generation and recombination. As a result, the J(sc) and FF are significantly improved. However, the smaller band gap and the higher HOMO level of TQ1 upon annealing causes a lower V-oc. The blend of an amorphous polymer TQ1, and a semi-crystalline polymer N2200, can thus be modified by thermal annealing to double the power conversion efficiency.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2016
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-127066 (URN)10.1039/c6ta00531d (DOI)000371967000030 ()
    Anmärkning

    Funding Agencies|Swedish Energy Agency; Swedish Research council, NSFC [21504006, 21534003]; Knut and Alice Wallenberg Foundation through a Wallenberg scholar grant; China Scholarship Council (CSC); graduate student short-term abroad research project of Jinan University; program for the Excellent Doctoral Dissertations of Guangdong Province [ybzzxm201114]; U.S. Department of Energy [DE-AC02-05CH11231]

    Tillgänglig från: 2016-04-13 Skapad: 2016-04-13 Senast uppdaterad: 2019-01-04
    2. Semitransparent all-polymer solar cells through lamination
    Öppna denna publikation i ny flik eller fönster >>Semitransparent all-polymer solar cells through lamination
    2018 (Engelska)Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 42, s. 21186-21192Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In this work, we demonstrate all-polymer solar cells where all the layers are made from polymers. We use PEDOT:PSS as the semitransparent anode and polyethyleneimine modified PEDOT:PSS as the semitransparent cathode, both of which are slot-die printed on polyethylene terephthalate (PET). Active layers are deposited on the cathode and anode surfaces by spin coating separately. These layers are then joined through a roll-to-roll compatible lamination process. This results in a semitransparent and flexible solar cell. We have used two polymer-polymer systems and several combinations, and the highest power conversion efficiency (PCE) obtained is 2.3% with a mean transparency amp;gt;35% within the visible light range. By laminating a thin layer acceptor polymer to a thick polymer-polymer blend, we can improve the performance by reducing recombination, compared to laminating blend to blend, which is verified by the trap-limited charge transport, CELIV and electroluminescence.

    Ort, förlag, år, upplaga, sidor
    ROYAL SOC CHEMISTRY, 2018
    Nationell ämneskategori
    Polymerkemi
    Identifikatorer
    urn:nbn:se:liu:diva-153535 (URN)10.1039/c8ta07992g (DOI)000451600200066 ()
    Anmärkning

    Funding Agencies|Swedish Energy Agency; Knut and Alice Wallenberg foundation (KAW); China Scholarship Council (CSC)

    Tillgänglig från: 2018-12-20 Skapad: 2018-12-20 Senast uppdaterad: 2019-03-25
    3. Large-Area, Semitransparent, and Flexible All-Polymer Photodetectors
    Öppna denna publikation i ny flik eller fönster >>Large-Area, Semitransparent, and Flexible All-Polymer Photodetectors
    Visa övriga...
    2018 (Engelska)Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 48, artikel-id 1805570Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Photodetectors, converting optical signals from specific wavelengths to electrical signals, have many applications on photoimaging, optical communication, and environmental monitoring. Solution-processed organic photodetectors (OPDs) based on organic materials emerge promise especially for wearable electronics and smart buildings. In this work, new all-polymer photodetectors (all-PPDs) are developed based on bulk-heterojunction active layers which incorporate a donor polymer and an acceptor polymer. The inverted all-PPDs exhibit outstanding external quantum efficiency over 70%, low dark current density (J(d)) of 1.1 x 10(-8) A cm(-2), and high detectivity (D*) over 3.0 x 10(12) Jones with planar response over the entire visible range. It is one of the best-performing all-PPDs reported so far and is also comparable with many organic and inorganic photodetectors. By using lamination technique, large-area, semitransparent, flexible, and "fully" polymeric photodetectors are successfully fabricated for the first time, with D* over 10(11) Jones for double-side light detection. The results highlight the great potential for producing high-performance all-PPDs by taking advantages of various device architecture and solution-processing techniques.

    Ort, förlag, år, upplaga, sidor
    WILEY-V C H VERLAG GMBH, 2018
    Nyckelord
    all-polymer photodetectors; conjugated polymers; flexible electronics; semitransparent electronics
    Nationell ämneskategori
    Materialkemi
    Identifikatorer
    urn:nbn:se:liu:diva-153367 (URN)10.1002/adfm.201805570 (DOI)000451118800014 ()
    Anmärkning

    Funding Agencies|Knut and Alice Wallenberg foundation through a Wallenberg Scholar grant; Ocean University of China; Ministry of Science and Technology [2016YFA0200700]; National Natural Science Foundation of China [21704082, 21875182, 21534003, 51320105014]; China Postdoctoral Science Foundation [2017M623162]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy [DE-AC02-05CH11231]; China Scholarship Council (CSC)

    Tillgänglig från: 2018-12-18 Skapad: 2018-12-18 Senast uppdaterad: 2019-01-04
  • 612.
    Xia, Yuxin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten. Jinan University, Peoples R China.
    Musumeci, Chiara
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Bergqvist, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ma, Wei
    Xi An Jiao Tong University, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Tang, Zheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Bai, Sai
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Jin, Yizheng
    Zhejiang University, Peoples R China.
    Zhu, Chenhui
    University of Calif Berkeley, CA 94720 USA.
    Kroon, Renee
    Zhejiang University, Peoples R China.
    Wang, Cheng
    University of Calif Berkeley, CA 94720 USA.
    Andersson, Mats R.
    University of S Australia, Australia.
    Hou, Lintao
    Jinan University, Peoples R China.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Wang, Ergang
    Chalmers, Sweden.
    Inverted all-polymer solar cells based on a quinoxaline-thiophene/naphthalene-diimide polymer blend improved by annealing2016Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 10, s. 3835-3843Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have investigated the effect of thermal annealing on the photovoltaic parameters of all-polymer solar cells based on a quinoxaline-thiophene donor polymer (TQ1) and a naphthalene diimide acceptor polymer (N2200). The annealed devices show a doubled power conversion efficiency compared to nonannealed devices, due to the higher short-circuit current (J(sc)) and fill factor (FF), but with a lower open circuit voltage (V-oc). On the basis of the morphology-mobility examination by several scanning force microscopy techniques, and by grazing-incidence wide-angle X-ray scattering, we conclude that better charge transport is achieved by higher order and better interconnected networks of the bulk heterojunction in the annealed active layers. The annealing improves charge transport and extends the conjugation length of the polymers, which do help in charge generation and meanwhile reduce recombination. Photoluminescence, electroluminescence, and light intensity dependence measurements reveal how this morphological change affects charge generation and recombination. As a result, the J(sc) and FF are significantly improved. However, the smaller band gap and the higher HOMO level of TQ1 upon annealing causes a lower V-oc. The blend of an amorphous polymer TQ1, and a semi-crystalline polymer N2200, can thus be modified by thermal annealing to double the power conversion efficiency.

  • 613.
    Xia, Yuxin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Xiaofeng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ever Aguirre, Luis
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Semitransparent all-polymer solar cells through lamination2018Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 42, s. 21186-21192Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work, we demonstrate all-polymer solar cells where all the layers are made from polymers. We use PEDOT:PSS as the semitransparent anode and polyethyleneimine modified PEDOT:PSS as the semitransparent cathode, both of which are slot-die printed on polyethylene terephthalate (PET). Active layers are deposited on the cathode and anode surfaces by spin coating separately. These layers are then joined through a roll-to-roll compatible lamination process. This results in a semitransparent and flexible solar cell. We have used two polymer-polymer systems and several combinations, and the highest power conversion efficiency (PCE) obtained is 2.3% with a mean transparency amp;gt;35% within the visible light range. By laminating a thin layer acceptor polymer to a thick polymer-polymer blend, we can improve the performance by reducing recombination, compared to laminating blend to blend, which is verified by the trap-limited charge transport, CELIV and electroluminescence.

  • 614.
    Xia, Yuxin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Xiaofeng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Ocean Univ China, Peoples R China.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Photovoltage loss in semi-transparent organic photovoltaic devices2019Ingår i: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 74, s. 37-40Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The use of semi-transparent photovoltaic devices causes an inevitable loss of photocurrent, as light transmitted has not been absorbed. This trivial effect also leads to a loss of photovoltage, an effect partially due to the lower photocurrent but also due to the geometry of the semi-transparent photovoltaic device. We here demonstrate and evaluate this photovoltage loss in semi-transparent organic photovoltaic devices, compared with non-transparent solar cells of the same material. Semi-transparent solar cells in addition introduce photovoltage loss when formed by lamination. We document and analyze these effects for a number of polymer blends in the form of bulk heterojunctions.

  • 615.
    Xiao, Huan
    et al.
    Nanjing University of Aeronaut and Astronaut, Peoples R China.
    Yang, Ying
    Nanjing University of Aeronaut and Astronaut, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Li, Qian
    Nanjing University of Aeronaut and Astronaut, Peoples R China.
    Meng, Han-qi
    Nanjing University of Aeronaut and Astronaut, Peoples R China.
    He, Wei
    Nanjing University of Aeronaut and Astronaut, Peoples R China.
    THE STUDY FOR FERROMAGNETIC PROPERTIES AND MICROSTRUCTURE OF Bi(0.9)Ho(0.1)FeO(3)2008Ingår i: PROCEEDINGS OF THE 2008 SYMPOSIUM ON PIEZOELECTRICITY, ACOUSTIC WAVES AND DEVICE APPLICATIONS, IEEE , 2008, s. 557-560Konferensbidrag (Refereegranskat)
    Abstract [en]

    Bi(0.9)Ho(0.1)FeO(3) ceramic is prepared by sol-gel method. We investigated the effect of Ho element doping in the BiFeO(3). We studied the microstructure, morphology and ferromagnetism for Bi(0.9)Ho(0.1)FeO(3) ceramic by XRD, SEM and SQUID. It shows that Bi(0.9)Ho(0.1)FeO(3) ceramic exhibits single phase of perovskite structure. The c/a rate is elevated from 1 to 1.009 with respect to BiFeO(3). The grains of Bi(0.9)Ho(0.1)FeO(3) ceramic shrink sharply compared with the ones of BiFeO(3) ceramic, which is beneficial to the connection between grains and the density. Bi(0.9)Ho(0.1)FeO(3) ceramic exhibits obvious ferromagnetism while BiFeO(3) ceramic does not possess the macroscopic ferromagnetism at the RT. The magnetization sinks in the horizontal direction near the zero magnetic field. It indicates that Bi(0.9)Ho(0.1)FeO(3) ceramics do not only show obvious ferromagnetism, but also could exhibit lower magnetic hysteresis loss.

  • 616.
    Xie, Shenkun
    et al.
    Beihang Univ, Peoples R China; Natl Ctr Nanosci and Technol, Peoples R China.
    Xia, Yuxin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zheng, Zhong
    Natl Ctr Nanosci and Technol, Peoples R China.
    Zhang, Xuning
    Beihang Univ, Peoples R China.
    Yuan, Jianyu
    Soochow Univ, Peoples R China.
    Zhou, Huiqiong
    Natl Ctr Nanosci and Technol, Peoples R China.
    Zhang, Yuan
    Beihang Univ, Peoples R China.
    Effects of Nonradiative Losses at Charge Transfer States and Energetic Disorder on the Open-Circuit Voltage in Nonfullerene Organic Solar Cells2018Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 5, artikel-id 1705659Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The considerable improvement on the power conversion efficiency (PCE) for emerging nonfullerene polymer solar cells is still limited by considerable voltage losses that have become one of the most significant obstacles in further boosting desired photovoltaic performance. Here, a comprehensive study is reported to understand the impacts of charge transport, energetic disorder, and charge transfer states (CTS) on the losses in open-circuit voltage (V-oc) based on three high performing bulk heterojunction solar cells with the best PCE exceeding 11%. It is found that the champion poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b]dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)-benzo[1,2-c:4,5-c]dithiophene-4,8-dione))] (PBDB-T):IT-M solar cell (PCE = 11.5%) is associated with the least disorder. The determined energetic disorder in part reconciles the difference in V-oc between the solar cells. A reduction is observed in the nonradiative losses (V-nonrad) coupled with the increase of energy of CTS for the PBDB-T:IT-M device, which may be related to the improved balance in carrier mobilities, and partially can explain the gain in V-oc. The determined radiative limit for V-oc combined with the V-nonrad generates an excellent agreement for the V-oc with the experimental values. The results suggest that minimizing the energetic disorder related to transport and CTS is critical for the mitigation of V-oc losses and improvements on the device performance.

  • 617.
    Xing, Xing
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Wang, Chuan Fei
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Leiqiang, Qin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Wang, Ergang
    Chalmers University of Technology, Sweden.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    The trade-off between electrochromic stability and contrast of a thiophene-Quinoxaline copolymer2017Ingår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 253, s. 530-535Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The stability of organic electrochromic devices is a crucial issue for their applications. However, until now the degradation mechanism of electrochromic materials are still not fully understood especially for electrochromic conjugated polymers (ECPs). To improve device stability, intensive investigation on the degradation mechanism of ECPs is urgently needed. Here we report our study on the electrochromic degradation in a thiophene-quinoxaline copolymer: poly [2,3-bis-(3-octyloxyphenyl) quinoxaline-5,8diyl- alt-thiophene-2,5-diyl] (TQ1). The results of X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectra (UPS) and UV-vis transmission spectra reveal that there are three main factors during the electrochromic degradation of TQ1. The first one is anion (ClO4-) irreversibly deep trapped, while the second is peroxidation of the thiophene group in TQ1. Both factors reduce the conductivity and electrochromism of TQ1. The third is structural relaxation resulting lager conjugated system of TQ1 molecules in film, which is gradually developed during 400 cycling of CV at a narrow potential range (01 V). When a potential range 0-0.7 V is applied, all three factors are prohibited, no electrochromism degradation is observed anymore, although the contrast becomes smaller. Our investigation systematically discloses the degradation mechanism during the electrochemistry processing of a ECP (TQ1), demonstrating the significance of trade-off between the electrochromic stability and contrast of the ECP. (C) 2017 Elsevier Ltd. All rights reserved.

  • 618.
    Xing, Xing
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zeng, Qi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Vagin, Mikhail
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Fast switching polymeric electrochromics with facile processed water dispersed nanoparticles2018Ingår i: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 47, s. 123-129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work, water dispersed electrochromic polymer nanoparticles (WDENs) prepared with miniemulsion process are introduced into electrochromic polymer (ECP) electrode for the first time. The poly [2, 3-bis-(3-octyloxyphenyl) quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl]) nanoparticle (NP) electrode shows much faster switching speed than the compacted electrode (e.g. 2.10 s vs. 24.15 s for coloring, 8.65 s vs. 25.95 s for bleaching @ 0.4 V; 1.30 s vs. 9.20 s coloring and 1.7 s vs. 2.90 s for bleaching @ 1.0 V). Moreover, the potentiality of WDENs for universal ECPs is demonstrated. The microelectrochemical measurement indicates much more efficient counter-ion diffusion between the electrolyte and the NP films than the compacted films, which results in much faster electrochromic switching. Besides the facile and eco-friendly processing of the WDENs, all solution and low cost fabrication of ECP NP films suggest their broad applications in commercial production of polymer electrochromic display and great potential for other polymer electrochemical electronics.

  • 619.
    Xu, Bo
    et al.
    KTH Royal Institute Technology, Sweden.
    Tian, Haining
    KTH Royal Institute Technology, Sweden; Uppsala University, Sweden.
    Lin, Lili
    Shandong Normal University, Peoples R China; KTH Royal Institute Technology, Sweden.
    Qian, Deping
    Chen, Hong
    Stockholm University, Sweden; Stockholm University, Sweden.
    Zhang, Jinbao
    Uppsala University, Sweden.
    Vlachopoulos, Nick
    Uppsala University, Sweden.
    Boschloo, Gerrit
    Uppsala University, Sweden.
    Luo, Yi
    KTH Royal Institute Technology, Sweden.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Hagfeldt, Anders
    Uppsala University, Sweden.
    Sun, Licheng
    KTH Royal Institute Technology, Sweden; Dalian University of Technology, Peoples R China.
    Integrated Design of Organic Hole Transport Materials for Efficient Solid-State Dye-Sensitized Solar Cells2015Ingår i: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 5, nr 3, artikel-id 1401185Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A series of triphenylamine-based small molecule organic hole transport materials (HTMs) with low crystallinity and high hole mobility are systematically investigated in solid-state dye-sensitized solar cells (ssDSCs). By using the organic dye LEG4 as a photosensitizer, devices with X3 and X35 as the HTMs exhibit desirable power conversion efficiencies (PCEs) of 5.8% and 5.5%, respectively. These values are slightly higher than the PCE of 5.4% obtained by using the state-of-the-art HTM Spiro-OMeTAD. Meanwhile, transient photovoltage decay measurement is used to gain insight into the complex influences of the HTMs on the performance of devices. The results demonstrate that smaller HTMs induce faster electron recombination in the devices and suggest that the size of a HTM plays a crucial role in device performance, which is reported for the first time.

  • 620.
    Xu, Weidong
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Tech Univ NanjingTech, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    The progress and prospects of non-fullerene acceptors in ternary blend organic solar cells2018Ingår i: Materials Horizons, ISSN 2051-6347, E-ISSN 2051-6355, Vol. 5, nr 2, s. 206-221Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The rapid development of organic solar cells (OSCs) based on non-fullerene acceptors has attracted increasing attention during the past few years, with a record power conversion efficiency of over 13% in a binary bulk heterojunction architecture. This exciting development also enables new possibilities for ternary OSCs to further enhance their efficiency and stability. This review summarizes very recent developments of ternary OSCs, with a focus on blends involving non-fullerene acceptors. We also highlight the challenges and perspectives for further development of ternary blend organic solar cells.

  • 621.
    Xu, Weidong
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), Nanjing, China.
    Hu, Qi
    Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), Nanjing, China.
    Bai, Sai
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Bao, Chunxiong
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology, Shenzhen University, Shenzhen, China.
    Miao, Yanfeng
    Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), Nanjing, China.
    Yuan, Zhongcheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Borzda, Tetiana
    Center for Nano Science and Technology @Polimi, Istituto Italiano di Tecnologia, Milan, Italy.
    Barker, Alex J.
    Center for Nano Science and Technology @Polimi, Istituto Italiano di Tecnologia, Milan, Italy.
    Tyukalova, Elizaveta
    School of Materials Science and Engineering, Nanyang Technological University (NTU), Singapore, Singapore.
    Hu, Zhang-Jun
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Kawecki, Maciej
    Laboratory for Nanoscale Materials Science, Empa, Dubendorf, Switzerland / Department of Physics, University of Basel, Basel, Switzerland.
    Wang, Heyong
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yan, Zhibo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, P. R. China.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Shi, Xiaobo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Uvdal, Kajsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Zhang, Wenjing
    International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology, Shenzhen University, Shenzhen, China.
    Duchamp, Martial
    School of Materials Science and Engineering, Nanyang Technological University (NTU), Singapore, Singapore.
    Liu, Jun-Ming
    Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, P. R. China.
    Petrozza, Annamaria
    Center for Nano Science and Technology @Polimi, Istituto Italiano di Tecnologia, Milan, Italy.
    Wang, Jianpu
    Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), Nanjing, China.
    Liu, Li-Min
    Beijing Computational Science Research Center, Beijing, China / chool of Physics, Beihang University, Beijing, China .
    Huang, Wei
    ey Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), Nanjing, China / Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), Xi’an, China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Rational molecular passivation for high-performance perovskite light-emitting diodes2019Ingår i: Nature Photonics, ISSN 1749-4885, E-ISSN 1749-4893, Vol. 13, nr 6, s. 418-424Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A major efficiency limit for solution-processed perovskite optoelectronic devices, for example light-emitting diodes, is trap-mediated non-radiative losses. Defect passivation using organic molecules has been identified as an attractive approach to tackle this issue. However, implementation of this approach has been hindered by a lack of deep understanding of how the molecular structures influence the effectiveness of passivation. We show that the so far largely ignored hydrogen bonds play a critical role in affecting the passivation. By weakening the hydrogen bonding between the passivating functional moieties and the organic cation featuring in the perovskite, we significantly enhance the interaction with defect sites and minimize non-radiative recombination losses. Consequently, we achieve exceptionally high-performance near-infrared perovskite light-emitting diodes with a record external quantum efficiency of 21.6%. In addition, our passivated perovskite light-emitting diodes maintain a high external quantum efficiency of 20.1% and a wall-plug efficiency of 11.0% at a high current density of 200 mA cm−2, making them more attractive than the most efficient organic and quantum-dot light-emitting diodes at high excitations.

    Publikationen är tillgänglig i fulltext från 2020-03-25 16:05
  • 622.
    Xu, Weidong
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Tech Univ NanjingTech, Peoples R China; Nanjing Tech Univ NanjingTech, Peoples R China.
    Lei, Gang
    Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Univ Posts and Telecommun, Peoples R China.
    Tao, Chen
    Wuhan Univ, Peoples R China.
    Zhang, Jiandong
    Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Univ Posts and Telecommun, Peoples R China.
    Liu, Xiaoke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Xiang
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Lai, Wen-Yong
    Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Univ Posts and Telecommun, Peoples R China; NPU, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Huang, Wei
    Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Univ Posts and Telecommun, Peoples R China; Nanjing Tech Univ NanjingTech, Peoples R China; Nanjing Tech Univ NanjingTech, Peoples R China; NPU, Peoples R China.
    Precisely Controlling the Grain Sizes with an Ammonium Hypophosphite Additive for High-Performance Perovskite Solar Cells2018Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 33, artikel-id 1802320Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A facile approach to precisely control the perovskite grain sizes is proposed and demonstrated for high-performance photovoltaic (PV) solar cells. With the introduction of various amounts of NH4H2PO2 (AHP) additives into the PbI2/CH3NH3I precursors, the grain scale of CH3NH3PbI3 films can be finely turned from hundreds of nanometer to micrometer scale, allowing evaluating the effects of crystalline grain boundary on trap densities, charge recombination, and PV device performance. The X-ray diffraction and X-ray photoelectron spectroscopy measurements indicate that the formation of intermediates plays a key role in assisting the perovskite crystal growth. The optimized devices show much larger open-circuit voltages (V-OC) up to 1.10 +/- 0.02 V and significantly enhance power conversion efficiencies (PCEs) of 16.5 +/- 0.7%, as compared to the control devices with PCE of 9.4 +/- 1.0% and V-OC of 1.00 +/- 0.03 V. Further investigations confirm that the boosted PV performance origins from the decreased defect densities due to enlarged grain sizes. It is also demonstrated that the approach is general and applicable to other perovskite systems, e.g., HC(NH2)(2)PbI3. The results suggest the promising application of AHP in achieving high-performance perovskite PV devices, and shed light on understanding the grain boundary effects on perovskite optoelectronics.

  • 623.
    Xu, Weidong
    et al.
    Soochow University, Peoples R China.
    McLeod, John A.
    Soochow University, Peoples R China.
    Yang, Yingguo
    Chinese Academic Science, Peoples R China.
    Wang, Yimeng
    Soochow University, Peoples R China; Beijing University of Technology, Peoples R China; Beijing University of Technology, Peoples R China.
    Wu, Zhongwei
    Soochow University, Peoples R China.
    Bai, Sai
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yuan, Zhongcheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Song, Tao
    Soochow University, Peoples R China.
    Wang, Yusheng
    Soochow University, Peoples R China; Beijing University of Technology, Peoples R China; Beijing University of Technology, Peoples R China.
    Si, Junjie
    Zhejiang University, Peoples R China.
    Wang, Rongbin
    Soochow University, Peoples R China.
    Gao, Xingyu
    Chinese Academic Science, Peoples R China.
    Zhang, Xinping
    Beijing University of Technology, Peoples R China; Beijing University of Technology, Peoples R China.
    Liu, Lijia
    Soochow University, Peoples R China.
    Sun, Baoquan
    Soochow University, Peoples R China.
    Iodomethane-Mediated Organometal Halide Perovskite with Record Photoluminescence Lifetime2016Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 8, nr 35, s. 23181-23189Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organometallic lead halide perovskites are excellent light harvesters for high-efficiency photovoltaic devices. However, as the key component in these devices, a perovskite thin film with good morphology and minimal trap states is still difficult to obtain. Herein we show that by incorporating a low boiling point alkyl halide such as iodomethane (CH3I) into the precursor solution, a perovskite (CH3NH3PbI3-xClx) film with improved grain size and orientation can be easily achieved. More importantly, these films exhibit a significantly reduced amount of trap states. Record photoluminescence lifetimes of more than 4 mu s are achieved; these lifetimes are significantly longer than that of pristine CH3NH3PbI3-xClx films. Planar heterojunction solar cells incorporating these CH3I-mediated perovskites have demonstrated a dramatically increased power conversion efficiency compared to the ones using pristine CH3NH3PbI3-xClx. Photoluminescence, transient absorption, and microwave detected photoconductivity measurements all provide consistent evidence that CH3I addition increases the number of excitons generated and their diffusion length, both of which assist efficient carrier transport in the photovoltaic device. The simple incorporation of alkyl halide to enhance perovskite surface passivation introduces an important direction for future progress on high efficiency perovskite optoelectronic devices.

  • 624.
    Xu, Xiaofeng
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Ocean Univ China, Peoples R China.
    Zhou, Xiaobo
    Xi An Jiao Tong Univ, Peoples R China.
    Zhou, Ke
    Xi An Jiao Tong Univ, Peoples R China.
    Xia, Yuxin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ma, Wei
    Xi An Jiao Tong Univ, Peoples R China.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Large-Area, Semitransparent, and Flexible All-Polymer Photodetectors2018Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 48, artikel-id 1805570Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Photodetectors, converting optical signals from specific wavelengths to electrical signals, have many applications on photoimaging, optical communication, and environmental monitoring. Solution-processed organic photodetectors (OPDs) based on organic materials emerge promise especially for wearable electronics and smart buildings. In this work, new all-polymer photodetectors (all-PPDs) are developed based on bulk-heterojunction active layers which incorporate a donor polymer and an acceptor polymer. The inverted all-PPDs exhibit outstanding external quantum efficiency over 70%, low dark current density (J(d)) of 1.1 x 10(-8) A cm(-2), and high detectivity (D*) over 3.0 x 10(12) Jones with planar response over the entire visible range. It is one of the best-performing all-PPDs reported so far and is also comparable with many organic and inorganic photodetectors. By using lamination technique, large-area, semitransparent, flexible, and "fully" polymeric photodetectors are successfully fabricated for the first time, with D* over 10(11) Jones for double-side light detection. The results highlight the great potential for producing high-performance all-PPDs by taking advantages of various device architecture and solution-processing techniques.

  • 625.
    Xu, Yalong
    et al.
    Soochow Univ, Peoples R China.
    Yuan, Jianyu
    Soochow Univ, Peoples R China.
    Liang, Shuyan
    Fudan Univ, Peoples R China.
    Chen, Jing-De
    Soochow Univ, Peoples R China.
    Xia, Yuxin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Larson, Bryon W.
    Natl Renewable Energy Lab, CO 80401 USA.
    Wang, Yusheng
    Soochow Univ, Peoples R China.
    Su, Gregory M.
    Lawrence Berkeley Natl Lab, CA 94720 USA.
    Zhang, Yannan
    Soochow Univ, Peoples R China.
    Cui, Chaohua
    Soochow Univ, Peoples R China.
    Wang, Ming
    Donghua Univ, Peoples R China.
    Zhao, Haibin
    Fudan Univ, Peoples R China.
    Ma, Wanli
    Soochow Univ, Peoples R China.
    Simultaneously Improved Efficiency and Stability in All-Polymer Solar Cells by a P-i-N Architecture2019Ingår i: ACS ENERGY LETTERS, ISSN 2380-8195, Vol. 4, nr 9, s. 2277-2286Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    All-polymer organic solar cells offer exceptional stability. Unfortunately, the use of bulk heterojunction (BHJ) structure has the intrinsic challenge to control the side-chain entanglement and backbone orientation to achieve sophisticated phase separation in all-polymer blends. Here, we revealed that the P-i-N structure can outperform the BHJ ones with a nearly 50% efficiency improvement, reaching a power conversion efficiency approaching 10%. This P-i-N structure can also provide an enhanced internal electric field and remarkably stable morphology Sequential deposition under harsh thermal stress. We have further demonstrated generality of the P-i-N structure in several other all-polymer systems. Considering the adjustable polymer molecular weight and solubility, the P-i-N device structure can be more beneficial for all-polymer systems. With the design of more crystalline polymers, the antiquated P-i-N structure can further show its strength in all-polymer systems by simplified morphology control and improved carrier extraction, becoming a more favorite device structure than the dominant BHJ structure.

  • 626.
    Xue-Jian, Xu
    et al.
    Tianjin University of Technology, Peoples R China .
    Yang, Li-Ying
    Tianjin University of Technology, Peoples R China .
    Tian, Hui
    Tianjin University of Technology, Peoples R China .
    Qin, Wen-Jing
    Tianjin University of Technology, Peoples R China .
    Yin, Shou-Gen
    Tianjin University of Technology, Peoples R China .
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan. Tianjin University of Technology, Peoples R China .
    Enhanced Performance and Stability in Polymer Photovoltaic Cells Using Ultraviolet-Treated PEDOT:PSS2013Ingår i: Chinese Physics Letters, ISSN 0256-307X, E-ISSN 1741-3540, Vol. 30, nr 7Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigate the effects of ultraviolet (UV) irradiation treatment with varying irradiation intensities for different treatment times of poly(3, 4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film on the performance and stability of polymer solar cells (PSCs) based on regioregular poly(3-hexylthiophene) (P3HT) and methanofullerene [6,6]-phenyl C-61-butyric acid methyl ester (PCBM) blend. Ultraviolet-visible transmission spectra, x-ray photoelectron spectroscopy, contact angle measurement, atomic force microscopy and the Kelvin probe method are conducted to characterize the UV-treated PEDOT:PSS film. The results demonstrate that UV treatment can improve the power conversion efficiency (PCE) and stability of PSCs effectively. The best performance is achieved under 1200 mu W/cm(2) UV treatment for 50 min. Compared to the control device, the optimized device exhibits enhanced performance with a V-OC of 0.59 V, J(SC) of 12.3 mA/cm(2), fill factor of 51%, and PCE of 3.64%, increased by 3.5%, 33%, 8.7% and 50%, respectively. The stability of the PSCs is enhanced by 2.5 times simply through the UV treatment on the PEDOT:PSS buffer layer. The improvement in the device performance and stability is attributed to the improvement in the wettability property and the increase in the work function of the PEDOT:PSS film by UV treatment, while the impact of UV treatment on the transparency of the PEDOT:PSS film is negligible. The strategy of using UV treatment to improve device performance and stability is attractive due to its simplicity, cost-effectiveness, and because it is suitable for large-scale commercial production.

  • 627.
    Yan, Han
    et al.
    Xi An Jiao Tong Univ, Peoples R China.
    Chen, Jianya
    Xi An Jiao Tong Univ, Peoples R China.
    Zhou, Ke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Xi An Jiao Tong Univ, Peoples R China.
    Tang, Yabing
    Xi An Jiao Tong Univ, Peoples R China.
    Meng, Xiangyi
    Xi An Jiao Tong Univ, Peoples R China.
    Xu, Xianbin
    Xi An Jiao Tong Univ, Peoples R China.
    Ma, Wei
    Xi An Jiao Tong Univ, Peoples R China.
    Lewis Acid Doping Induced Synergistic Effects on Electronic and Morphological Structure for Donor and Acceptor in Polymer Solar Cells2018Ingår i: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 8, nr 19, artikel-id 1703672Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to the attraction of optimizing the electronic structure beyond chemical synthesis, molecular doping has recently aroused wide interest in the field of organic solar cells. However, the selection of limited dopants confines its successful application. Inspired by the Lewis base characteristics of the photovoltaic materials, the Lewis acid as novel dopant is introduced in organic solar cells. In both fullerene and nonfullerene based blends, Lewis acid doping leads to increased photovoltaic performance. Detailed experiments reveal that Lewis acid doping has a synergistic effect on modifying the polymers electronic properties and the acceptors nanostructure even at low doping concentration, and these are simultaneously responsible for the device improvements. Based on the mechanism studies, it is proposed that the Lewis acid-doped polymers anions produce induced dipole on the acceptor, this increases the intermolecular interaction and facilitates the morphology optimization. It is believed that the synergistic effect by Lewis acid doping greatly expands the application of doped organic solar cells, in concert with other existing methods to yield higher efficiency values.

  • 628.
    Yan-Fang, Li
    et al.
    Tianjin University of Technology, China .
    Yang, Li-Ying
    Tianjin University of Technology, .
    Qin, Wen-Jing
    Tianjin University of Technology, .
    Yin, Shou-Gen
    Tianjin University of Technology, .
    Zhang, Feng-Ling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Efficiency Enhancement of MEH-PPV: PCBM Solar Cells by Addition of Ditertutyl Peroxide as an Additive2013Ingår i: Chinese Physics Letters, ISSN 0256-307X, E-ISSN 1741-3540, Vol. 30, nr 1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Improved power conversion efficiency (PCE) and stability of organic bulk heterojunction (BHJ) solar cells based on poly (2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV) and methanofullerene [6,6]-phenyl C-61-butyric acid methyl ester (PCBM) blends are obtained by using ditert butyl peroxide (DTBP) as an additive. The effect of the DTBP contents on the performance of photovoltaic cells is investigated. The results reveal that efficiency enhancement of MEH-PPV: PCBM solar cells can be realized by carefully tuning the contents of DTBP. Compared to the control device, the optimized device with 0.5wt% DTBP additive exhibits enhanced performance with J(sc) of (3.51 +/- 0.21) mA/cm(2), FF of (44.45 +/- 0.71)%, and PCE of (1.31 +/- 0.08)%, increased by 9.3%, 8.0% and 22.4%, respectively. The stability of the device is found to be improved by adding 0.5wt% of DTBP.

  • 629.
    Yang, Daobin
    et al.
    Yamagata Univ, Japan; Yamagata Univ, Japan.
    Wang, Yuming
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Sano, Takeshi
    Yamagata Univ, Japan; Yamagata Univ, Japan; Yamagata Univ, Japan.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Sasabe, Hisahiro
    Yamagata Univ, Japan; Yamagata Univ, Japan; Yamagata Univ, Japan.
    Kido, Junji
    Yamagata Univ, Japan; Yamagata Univ, Japan; Yamagata Univ, Japan.
    A minimal non- radiative recombination loss for efficient non- fullerene all- small- molecule organic solar cells with a low energy loss of 0.54 eV and high open- circuit voltage of 1.15 V+2018Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 28, s. 13918-13924Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organic solar cells (OSCs) are considered as a promising next-generation photovoltaic technology because of their light weight, flexibility, and the potential of roll-to-roll fabrication. However, the relatively large energy loss (E-loss) from the optical bandgap (E-g) of the absorber to the open-circuit voltage (V-oc) of the device hinders further improvement of the PCEs of OSCs. Here, we report efficient non-fullerene all-small-molecule organic solar cells (NF all-SMOSCs), using DR3TBDTT and O-IDTBR as the donor and acceptor, respectively. We obtain a high electroluminescence yield (EQE(EL)) value of up to approximate to 4 x 10(-4) corresponding to a 0.21 eV non-radiative recombination loss, which is the smallest value for bulk-heterojunction (BHJ) OSCs so far. As a result, a low E-loss of 0.54 eV and a considerably high V-oc of 1.15 V are obtained for BHJ NF all-SMOSCs.

  • 630.
    Yang, Fan
    et al.
    Chinese Academic Science, Peoples R China; University of Chinese Academic Science, Peoples R China.
    Qian, Deping
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Hesham Balawi, Ahmed
    KAUST, Saudi Arabia.
    Wu, Yang
    Xi An Jiao Tong University, Peoples R China.
    Ma, Wei
    Xi An Jiao Tong University, Peoples R China.
    Laquai, Frederic
    KAUST, Saudi Arabia.
    Tang, Zheng
    Technical University of Dresden, Germany.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Li, Weiwei
    Chinese Academic Science, Peoples R China.
    Performance limitations in thieno[3,4-c] pyrrole4,6-dione-based polymer: ITIC solar cells2017Ingår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, nr 35, s. 23990-23998Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report a systematic study of the efficiency limitations of non-fullerene organic solar cells that exhibit a small energy loss (E-loss) between the polymer donor and the non-fullerene acceptor. To clarify the impact of Eloss on the performance of the solar cells, three thieno[3,4-c] pyrrole-4,6-dione-based conjugated polymers (PTPD3T, PTPD2T, and PTPDBDT) are employed as the electron donor, which all have complementary absorption spectra compared with the ITIC acceptor. The corresponding photovoltaic devices show that low Eloss (0.54 eV) in PTPDBDT: ITIC leads to a high open-circuit voltage (Voc) of 1.05 V, but also to a small quantum efficiency, and in turn photocurrent. The high Voc or small energy loss in the PTPDBDT-based solar cells is a consequence of less non-radiative recombination, whereas the low quantum efficiency is attributed to the unfavorable micro-phase separation, as confirmed by the steady-state and time-resolved photoluminescence experiments, grazing-incidence wide-angle X-ray scattering, and resonant soft X-ray scattering (R-SoXS) measurements. We conclude that to achieve high performance non-fullerene solar cells, it is essential to realize a large Voc with small Eloss while simultaneously maintaining a high quantum efficiency by manipulating the molecular interaction in the bulk-heterojunction.

  • 631.
    Yang, Jianming
    et al.
    East China Normal Univ, Peoples R China.
    Hong, Qiuming
    Soochow Univ, Peoples R China.
    Yuan, Zhongcheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Ruipeng
    Soochow Univ, Peoples R China.
    Guo, Xuewen
    East China Normal Univ, Peoples R China.
    Xiong, Shaobing
    East China Normal Univ, Peoples R China.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Braun, Slawomir
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Li, Yanqing
    Soochow Univ, Peoples R China.
    Tang, Jianxin
    Soochow Univ, Peoples R China.
    Duan, Chungang
    East China Normal Univ, Peoples R China; Shanxi Univ, Peoples R China.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Bao, Qinye
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten. East China Normal Univ, Peoples R China; Shanxi Univ, Peoples R China; Soochow Univ, Peoples R China.
    Unraveling Photostability of Mixed Cation Perovskite Films in Extreme Environment2018Ingår i: Advanced Optical Materials, ISSN 2162-7568, E-ISSN 2195-1071, Vol. 6, nr 20, artikel-id 1800262Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organometal halide perovskites exhibit a bright future for applications in solar cells, as efficiency has achieved over 22%. The long-term stability remains a major obstacle for commercialization. Here, it is found that three cationic compositional engineered perovskites, MAPb(I0.83Br0.17)(3), FA(0.83)MA(0.17)Pb(I0.83Br0.17)(3), and Cs-0.1(FA(0.83)MA(0.17))(0.9)Pb(I0.83Br0.17)(3), undergo severe degradation under white-light illumination in ultrahigh vacuum (UHV) environment, but the rate of degradation is significantly lower for the mixed cation perovskites. This is attributed to the defect-induced trap states that trigger the strong coupling between the photoexcited carriers and the crystal lattice. The observed behavior supports the view of the mixed cations suppressing the photoinduced degradation. It is further demonstrated that UHV environment remarkably accelerates the degradation of the perovskite films under illumination, which delivers a very important message that the current hybrid perovskite materials and their optoelectronic devices are not suitable for application in outer space. Moreover, the applied UHV environment can be an accelerated test method to estimate the photostability of the perovskites.

  • 632.
    Yang, Jie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Shenzhen Univ, Peoples R China.
    Bao, Chunxiong
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Shenzhen Univ, Peoples R China.
    Ning, Weihua
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Tech Univ, Peoples R China.
    Wu, Bo
    Nanyang Technol Univ, Singapore.
    Ji, Fuxiang
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yan, Zhibo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Univ, Peoples R China.
    Tao, Youtian
    Nanjing Tech Univ, Peoples R China.
    Liu, Jun-Ming
    Nanjing Univ, Peoples R China.
    Sum, Tze Chien
    Nanyang Technol Univ, Singapore.
    Bai, Sai
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Wang, Jianpu
    Nanjing Tech Univ, Peoples R China.
    Huang, Wei
    Nanjing Tech Univ, Peoples R China.
    Zhang, Wenjing
    Shenzhen Univ, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Stable, High-Sensitivity and Fast-Response Photodetectors Based on Lead-Free Cs2AgBiBr6 Double Perovskite Films2019Ingår i: Advanced Optical Materials, ISSN 2162-7568, E-ISSN 2195-1071, Vol. 7, nr 13, artikel-id 1801732Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Solution-processed metal halide perovskites (MHPs) have demonstrated great advances on achieving high-performance photodetectors. However, the intrinsic material instability and the toxicity of lead still hinder the practical applications of MHPs-based photodetectors. In this work, the first highly sensitive and fast-response lead-free perovskite photodetectors based on Cs2AgBiBr6 double perovskite films are demonstrated. A convenient solution method is developed to deposit high-quality Cs2AgBiBr6 film with large grain sizes, low trap densities, and long charge carrier lifetimes. Incorporated within a photodiode device architecture comprised of optimized hole- and electron-transporting layers, lead-free perovskite photodetectors are achieved exhibiting a high detectivity of 3.29 x 10(12) Jones, a large linear dynamic range of 193 dB, and a fast response time of approximate to 17 ns. All the key figures of merit of the devices are comparable with the reported best-performing photodetectors based on lead halide perovskites. In addition, the resulting devices exhibit excellent thermal and environmental stability. The nonencapsulated devices show negligible degradation after thermal stressing at 150 degrees C and less than 5% degradation in the photoresponsivity after storage in ambient air for approximate to 2300 h. The results demonstrate the great potential of the lead-free Cs2AgBiBr6 double perovskite in applications for environmentally friendly and high-performance photodetectors.

  • 633.
    Yang, Jie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. University of Politecn Cataluna, Spain.
    Roa, J. J.
    University of Politecn Cataluna, Spain; University of Politecn Cataluna, Spain.
    Schwin, M.
    SECO Tools AB, Sweden.
    Odén, Magnus
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska fakulteten.
    Johansson, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska fakulteten. SECO Tools AB, Sweden.
    Llanes, L.
    University of Politecn Cataluna, Spain; University of Politecn Cataluna, Spain.
    Grinding-induced metallurgical alterations in the binder phase of WC-Co cemented carbides2017Ingår i: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 134, s. 302-310Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The metallic binder phase dictates the toughening behavior of WC-Co cemented carbides (hardmetals), even though it occupies a relative small fraction of the composite. Studies on deformation and phase transformation of the binder constituent are scarce. Grinding represents a key manufacturing step in machining of hardmetal tools, and is well-recognized to induce surface integrity alterations. In this work, metallurgical alterations of the binder phase in ground WC-Co cemented carbides have been assessed by a combination of electron back scattered diffraction and transmission electron microscopy techniques. The Co-base binder experiences a martensitic phase transformation from fcc to hcp crystal structure, predominantly in the first 5 mu m below the surface. The hcp fraction decreases gradually along a depth of 10 mu m. Surface Co displays severe plastic deformation under the highest strain, resulting in formation of nanocrystalline grains in the first micrometer below the surface. Microstructural refinement within the binder phase is observed even at greater depth. Stacking faults were detected in most of the refined grains. The metallurgical alterations of the binder phase modify the local stress distribution during grinding, which affects the discerned subsurface microcracking. The resulting residual stress profile is the sum of multiple subsurface changes, such as phase transformation, severe plastic deformation and grain refinement, where it is discerned that the depth profile of the transformed hcp-Co fraction coincides with the grinding-induced residual stress profile.

  • 634.
    Yang, Jie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. University of Politecn Cataluna, Spain.
    Roa, J. J.
    University of Politecn Cataluna, Spain; University of Politecn Cataluna, Spain.
    Schwind, M.
    SECO Tools AB, Sweden.
    Odén, Magnus
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska fakulteten.
    Johansson-Jõesaar, Mats P.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska fakulteten. SECO Tools AB, Sweden.
    Esteve, J.
    University of Barcelona, Spain.
    Llanes, L.
    University of Politecn Cataluna, Spain.
    Thermally induced surface integrity changes of ground WC-Co hardmetals2016Ingår i: 3RD CIRP CONFERENCE ON SURFACE INTEGRITY, Elsevier, 2016, Vol. 45, s. 91-94Konferensbidrag (Refereegranskat)
    Abstract [en]

    Ground hardmetals are exposed to high temperatures during both processing (e.g. coating deposition) and use (e.g. as a cutting tool). However, studies on thermally induced changes of surface integrity are limited. Here we address this by means of FIB/FESEM and EBSD investigation, with special focus on the binder phase characterization. Our findings indicate that thermal treatment causes two main surface modifications. First, an unexpected microporosity appears in the binder within the subsurface layer when ground surfaces are heated. Second, the metallic phase underneath the ground surface experiences metallurgical changes, in terms of grain and crystallographic phase structures. The mechanisms responsible for these modifications of the binder are discussed in terms of grinding-induced and thermally-reversed phase transformation as well as recrystallization phenomena. We also note that no additional heat treatment related changes such as microcracking and carbide fragmentation in the subsurface layer, are discerned. (C) 2016 The Authors. Published by Elsevier B.V.

  • 635.
    Yang, Jie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Univ Politecn Cataluna, Spain; AMES Sintered Met Components, Spain.
    Roa, J. J.
    Univ Politecn Cataluna, Spain; Univ Politecn Cataluna, Spain.
    Schwind, M.
    SECO Tools AB, Sweden.
    Odén, Magnus
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska fakulteten.
    Johansson-Jöesaar, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska fakulteten.
    Esteve, J.
    Univ Barcelona, Spain.
    Llanes, L.
    Univ Politecn Cataluna, Spain; Univ Politecn Cataluna, Spain.
    Implementation of advanced characterisation techniques for assessment of grinding effects on the surface integrity of WC-Co cemented carbides2018Ingår i: Powder Metallurgy, ISSN 0032-5899, E-ISSN 1743-2901, Vol. 61, nr 2, s. 100-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Grinding is a key step on the manufacturing process of WC-Co cemented carbides (hardmetals). In this work, an investigation of grinding effects on the surface integrity of hardmetals is conducted. It is done by combining diverse advanced characterisation techniques: X-ray diffraction, field emission-scanning electron microscopy, electron back scatter diffraction, focused ion beam - 3D tomography and transmission electron microscopy. The study is carried out in a fine-grained WC-Co grade. Besides ground state, polished surface finish condition is assessed for comparison purposes. It is evidenced that grinding induces significant alterations: 3D tomography illustrates microcracking exists down to 2.5 mu m depth with a highly anisotropic distribution at the subsurface, large compressive residual stresses extending until subsurface levels of about 12 mu m, and phase transformation of binder from the original fcc phase into the hcp one, as well as severe plastic deformation observed within the binder at the surface level.

  • 636.
    Yang, Junyu
    et al.
    Jinan Univ, Peoples R China.
    Lin, Yuanbao
    Jinan Univ, Peoples R China.
    Zheng, Wenhao
    Jinan Univ, Peoples R China.
    Liu, Alei
    Jinan Univ, Peoples R China.
    Cai, Wanzhu
    Jinan Univ, Peoples R China.
    Yu, Xiaomin
    Jinan Univ, Peoples R China.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Jinan Univ, Peoples R China.
    Liang, Quanbin
    South China Univ Technol, Peoples R China.
    Wu, Hongbin
    South China Univ Technol, Peoples R China.
    Qin, Donghuan
    South China Univ Technol, Peoples R China.
    Hou, Lintao
    Jinan Univ, Peoples R China.
    Roll-to-Roll Slot-Die-Printed Polymer Solar Cells by Self-Assembly2018Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, nr 26, s. 22485-22494Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Extremely simplified one-step roll-to-roll slot-die-printed flexible indium tin oxide (ITO)-free polymer solar cells (PSCs) are demonstrated based on the ternary blends of electron-donor polymer thieno[3,4-b]thiophene/benzodithiophene, electron-acceptor fullerene [6,6]-phenyl-C-71-butyric acid methyl ester, and electron-extracting polymer poly[(9,9-bis(3-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) at room temperature (RT) in ambient air. The flexible ITO-free PSC exhibits a comparable power conversion efficiency (PCE) with the device employing complicated two-step slot-die printing (5.29% vs 5.41%), which indicates that PFN molecules can migrate from the ternary nanocomposite toward the Ag cathode via vertical self-assembly during the one-step slot-die printing process in air. To confirm the migration of PFN, the morphology and elemental analysis as well as charge transport of different active layers are investigated by the in situ transient film drying process, transmission electron microscopy, atomic force microscopy, contact angle and surface energy, X-ray photoelectron spectroscopy, scanning electron microscopy, impedance spectroscopy, transient photovoltage and transient photocurrent, and laser-beam-induced current. Moreover, the good air and mechanical stability of the flexible device with a decent PCE achieved in 1 cm(2) PSCs at RT in air suggests the feasibility of energy-saving and time-saving one-step slot-die printing to large-scale roll-to-roll manufacture in the future.

  • 637.
    Yang, Lei
    et al.
    Univ Chinese Acad Sci, Peoples R China; Imperial Coll London, England.
    Qin, Linqing
    Univ Chinese Acad Sci, Peoples R China.
    Xu, Yunxiao
    Univ Chinese Acad Sci, Peoples R China.
    Zhang, Huotian
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Lv, Lei
    Univ Chinese Acad Sci, Peoples R China.
    Chen, Kepeng
    Dalian Univ Technol, Peoples R China.
    Sui, Xinyu
    Natl Ctr Nanosci and Technol, Peoples R China.
    Zhong, Yangguang
    Natl Ctr Nanosci and Technol, Peoples R China.
    Guo, Yuan
    Chinese Acad Sci, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhao, Jianzhang
    Dalian Univ Technol, Peoples R China.
    Li, Yuhao
    Chinese Univ Hong Kong, Peoples R China.
    Liu, Xinfeng
    Natl Ctr Nanosci and Technol, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Yi, Yuanping
    Chinese Acad Sci, Peoples R China.
    Lu, Xinhui
    Chinese Univ Hong Kong, Peoples R China.
    Peng, Aidong
    Univ Chinese Acad Sci, Peoples R China.
    Huang, Hui
    Univ Chinese Acad Sci, Peoples R China.
    Sulfur vs. tellurium: the heteroatom effects on the nonfullerene acceptors2019Ingår i: Science in China Series B: Chemistry, ISSN 1674-7291, E-ISSN 1869-1870, Vol. 62, nr 7, s. 897-903Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effect of chalcogen heteroatom variation on donor materials has been systematically investigated. However, this effect on acceptors has rarely been explored. Herein, nonfullerene acceptors BFPSP and BFPTP were reported by simply changing the chalcogen atoms from S to Te. The differences between BFPSP and BFPTP in light absorption, energy levels, excited-state lifetimes, energy loss, charge mobilities, morphology, and photovoltaic properties were systematically investigated to understand the heteroatom effects. More importantly, the electroluminescence spectra, external quantum efficiency of photovoltaics and TD-DFT calculations revealed that the triplet excited state (T-1) in energy of BFPTP equals to the charge transfer (CT) state in PBDB-T:BFPTP, which allows T-1 excitons, generated by intersystem crossing, to split into free charges to contribute to the efficiency. This contribution provides a strategy for tuning the photophysical properties of nonfullerene acceptors and designing high performance triplet materials for OSCs.

  • 638.
    Yang, Liying
    et al.
    Tianjin University Technology.
    Xu, Hao
    Tianjin University Technology.
    Tian, Hui
    Tianjin University Technology.
    Yin, Shougen
    Tianjin University Technology.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Effect of cathode buffer layer on the stability of polymer bulk heterojunction solar cells2010Ingår i: SOLAR ENERGY MATERIALS AND SOLAR CELLS, ISSN 0927-0248, Vol. 94, nr 10, s. 1831-1834Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effect of cathode buffer layer on the stability of polymer solar cells with cesium carbonate (Cs2CO3) as the cathode buffer layer was investigated. Compared with traditional devices using lithium fluoride (LiF) as buffer layer, the use of the Cs2CO3 layer has enhanced not only open-circuit voltages and power conversion efficiencies of the polymer solar cells due to better contact with the cathode but also the device stability. From results of stability test, we concluded that the inserted Cs2CO3 buffer layer is working as a better shielding and scavenging protector which prevents the intruding of oxygen and humidity into the active layer, thereby improving the lifetime of unpackaged devices.

  • 639.
    Yang Nilsson, Ting
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Wagner, Michal
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Lignin Modification for Biopolymer/Conjugated Polymer Hybrids as Renewable Energy Storage Materials2015Ingår i: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 8, nr 23, s. 4081-4085Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Lignin derivatives, which arise as waste products from the pulp and paper industry and are mainly used for heating, can be used as charge storage materials. The charge storage function is a result of the quinone groups formed in the lignin derivative. Herein, we modified lignins to enhance the density of such quinone groups by covalently linking monolignols and quinones through phenolation. The extra guaiacyl, syringyl, and hydroquinone groups introduced by phenolation of kraft lignin derivatives were monitored by P-31 nuclear magnetic resonance and size exclusion chromatography. Electropolymerization in ethylene glycol/tetraethylammonium tosylate electrolyte was used to synthesize the kraft lignin/polypyrrole hybrid films. These modifications changed the phenolic content of the kraft lignin with attachment of hydroquinone units yielding the highest specific capacity (around 70mAhg(-1)). The modification of softwood and hardwood lignin derivatives yielded 50% and 23% higher charge capacity than the original lignin, respectively.

  • 640.
    Yang, Rong
    et al.
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Li, Renzhi
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Cao, Yu
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Wei, Yingqiang
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Miao, Yanfeng
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Tan, Wen Liang
    Monash Univ, Australia.
    Jiao, Xuechen
    Monash Univ, Australia; Australian Synchrotron ANSTO, Australia.
    Chen, Hong
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Zhang, Liangdong
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Chen, Qing
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Zhang, Huotian
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zou, Wei
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Wang, Yuming
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yang, Ming
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Yi, Chang
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Wang, Nana
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    McNeill, Christopher R.
    Monash Univ, Australia.
    Qin, Tianshi
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Wang, Jianpu
    Nanjing Tech Univ NanjingTech, Peoples R China.
    Huang, Wei
    Nanjing Tech Univ NanjingTech, Peoples R China; NPU, Peoples R China.
    Oriented Quasi-2D Perovskites for High Performance Optoelectronic Devices2018Ingår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 30, nr 51, artikel-id 1804771Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quasi-2D layered organometal halide perovskites have recently emerged as promising candidates for solar cells, because of their intrinsic stability compared to 3D analogs. However, relatively low power conversion efficiency (PCE) limits the application of 2D layered perovskites in photovoltaics, due to large energy band gap, high exciton binding energy, and poor interlayer charge transport. Here, efficient and water-stable quasi-2D perovskite solar cells with a peak PCE of 18.20% by using 3-bromobenzylammonium iodide are demonstrated. The unencapsulated devices sustain over 82% of their initial efficiency after 2400 h under relative humidity of approximate to 40%, and show almost unchanged photovoltaic parameters after immersion into water for 60 s. The robust performance of perovskite solar cells results from the quasi-2D perovskite films with hydrophobic nature and a high degree of electronic order and high crystallinity, which consists of both ordered large-bandgap perovskites with the vertical growth in the bottom region and oriented small-bandgap components in the top region. Moreover, due to the suppressed nonradiative recombination, the unencapsulated photovoltaic devices can work well as light-emitting diodes (LEDs), exhibiting an external quantum efficiency of 3.85% and a long operational lifetime of approximate to 96 h at a high current density of 200 mA cm(-2) in air.

  • 641.
    Yang, Rong
    et al.
    Nanjing Technical University, Peoples R China.
    Zhang, Li
    Nanjing Technical University, Peoples R China.
    Cao, Yu
    Nanjing Technical University, Peoples R China.
    Miao, Yanfeng
    Nanjing Technical University, Peoples R China.
    Ke, You
    Nanjing Technical University, Peoples R China.
    Wei, Yingqiang
    Nanjing Technical University, Peoples R China.
    Guo, Qiang
    Nanjing Technical University, Peoples R China.
    Wang, Ying
    Nanjing Technical University, Peoples R China.
    Rong, Zhaohua
    Nanjing Technical University, Peoples R China.
    Wang, Nana
    Nanjing Technical University, Peoples R China.
    Li, Renzhi
    Nanjing Technical University, Peoples R China.
    Wang, Jianpu
    Nanjing Technical University, Peoples R China.
    Huang, Wei
    Nanjing Technical University, Peoples R China; Nanjing University of Posts and Telecommun, Peoples R China; Nanjing University of Posts and Telecommun, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Inhomogeneous degradation in metal halide perovskites2017Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 111, nr 7, artikel-id 073302Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although the rapid development of organic-inorganic metal halide perovskite solar cells has led to certified power conversion efficiencies of above 20%, their poor stability remains a major challenge, preventing their practical commercialization. In this paper, we investigate the intrinsic origin of the poor stability in perovskite solar cells by using a confocal fluorescence microscope. We find that the degradation of perovskite films starts from grain boundaries and gradually extend to the center of the grains. Firmly based on our findings, we further demonstrate that the device stability can be significantly enhanced by increasing the grain size of perovskite crystals. Our results have important implications to further enhance the stability of optoelectronic devices based on metal halide perovskites. Published by AIP Publishing.

  • 642.
    Yang, Yi
    et al.
    Chinese Academy of Science.
    Zhang, Jing
    Chinese Academy of Science.
    Zhou, Ye
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Zhao, Guangjin
    Chinese Academy of Science.
    He, Chang
    Chinese Academy of Science.
    Li, Yongfang
    Chinese Academy of Science.
    Andersson, Mattias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Solution-Processable Organic Molecule with Triphenylamine Core and Two Benzothiadiazole-Thiophene Arms for Photovoltaic Application2010Ingår i: JOURNAL OF PHYSICAL CHEMISTRY C, ISSN 1932-7447, Vol. 114, nr 8, s. 3701-3706Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new solution-processable biarmed organic molecule With triphenylamine (TPA) core and benzothiadiazole-hexylthiophene (BT-HT) arms, B(TPA-BT-HT), has been synthesized by a Heck reaction, and characterized by UV-vis absorption, cyclic voltammetry, and theoretical calculation. Photovoltaic properties of B(TPA-BT-HT) as light-harvesting and electron-donating material in organic solar cells (OSCs), with [6,6]-phenyl-C61-butyric acid methyl ester (PC60BM) or [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM) as acceptors, were systematically investigated. The performance of the OSCs varied significantly with B(TPA-BT-HT)/fullerene weight ratio, active layer thickness, and solvents Used For spin-coating the active layer. The optimized device with the B(TPA-BT-HT)/PC70BM weight ratio of 1:2 and a thickness of 55 nm with the active layer spin-coated from DCB solution Shows a power conversion efficiency of 1.96% with a short-circuit current density of 5.50 mA/cm(2) and in open-circuit voltage of 0.96 V under (lie illumination of AM 1.5, 100 mw/cm(2).

  • 643.
    Yang, Jianming
    et al.
    East China Normal Univ, Peoples R China.
    Yuan, Zhongcheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Braun, Slawomir
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Li, Yanqing
    Soochow Univ, Peoples R China.
    Tang, Jianxin
    Soochow Univ, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Duan, Chungang
    East China Normal Univ, Peoples R China; Shanxi Univ, Peoples R China.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Bao, Qinye
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten. East China Normal Univ, Peoples R China.
    Oxygen- and Water-Induced Energetics Degradation in Organometal Halide Perovskites2018Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, nr 18, s. 16225-16230Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organometal halide perovskites are under rapid development, and significant focus has been placed on their stability that currently presents a major obstacle for practical application. Energetics plays a vital role in charge injection/extraction and transport properties in devices. Here, we in situ investigate oxygen and water-induced energetics degradation in organometal halide perovskite films. Oxygen gas induces an upward shift of the vacuum level of the perovskite films because of the formation of an oxygen induced surface dipole, water vapor causes a significant vacuum-level downshift, and the valence band binding energy referenced to the Fermi level simultaneously increases so as to keep the ionization potential of the perovskite films unchanged. Moreover, the chemical compositions, crystalline structures, surface morphologies, and dynamical properties also are monitored and analyzed in detail. These results are indispensable to understand the degradation mechanisms and to perform the optimizations of stable materials and devices in the future.

  • 644.
    Yao, Huifeng
    et al.
    Chinese Acad Sci, Peoples R China.
    Cui, Yong
    Univ Chinese Acad Sci, Peoples R China.
    Qian, Deping
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ponseca, Carlito
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Honarfar, Alireza
    Lund Univ, Sweden.
    Xu, Ye
    Univ Chinese Acad Sci, Peoples R China.
    Xin, Jingming
    Xi An Jiao Tong Univ, Peoples R China.
    Chen, Zhenyu
    Xi An Jiao Tong Univ, Peoples R China.
    Hong, Ling
    Univ Chinese Acad Sci, Peoples R China.
    Gao, Bowei
    Univ Chinese Acad Sci, Peoples R China.
    Yu, Runnan
    Univ Chinese Acad Sci, Peoples R China.
    Zu, Yunfei
    Univ Chinese Acad Sci, Peoples R China.
    Ma, Wei
    Xi An Jiao Tong Univ, Peoples R China.
    Chabera, Pavel
    Lund Univ, Sweden.
    Pullerits, Tonu
    Lund Univ, Sweden.
    Yartsev, Arkady
    Lund Univ, Sweden.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Hou, Jianhui
    Univ Chinese Acad Sci, Peoples R China.
    14.7% Efficiency Organic Photovoltaic Cells Enabled by Active Materials with a Large Electrostatic Potential Difference2019Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 141, nr 19, s. 7743-7750Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although significant improvements have been achieved for organic photovoltaic cells (OPVs), the top-performing devices still show power conversion efficiencies far behind those of commercialized solar cells. One of the main reasons is the large driving force required for separating electron-hole pairs. Here, we demonstrate an efficiency of 14.7% in the single-junction OPV by using a new polymer donor PTO2 and a nonfullerene acceptor IT-4F. The device possesses an efficient charge generation at a low driving force. Ultrafast transient absorption measurements probe the formation of loosely bound charge pairs with extended lifetime that impedes the recombination of charge carriers in the blend. The theoretical studies reveal that the molecular electrostatic potential (ESP) between PTO2 and IT-4F is large, and the induced intermolecular electric field may assist the charge generation. The results suggest OPVs have the potential for further improvement by judicious modulation of ESP.

  • 645.
    Yao, Huifeng
    et al.
    Chinese Acad Sci, Peoples R China.
    Qian, Deping
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhang, Hao
    Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Qin, Yunpeng
    Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Xu, Bowei
    Chinese Acad Sci, Peoples R China.
    Cui, Yong
    Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Yu, Runnan
    Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Hou, Jianhui
    Chinese Acad Sci, Peoples R China; Univ Chinese Acad Sci, Peoples R China.
    Critical Role of Molecular Electrostatic Potential on Charge Generation in Organic Solar Cells2018Ingår i: Chinese journal of chemistry, ISSN 1001-604X, E-ISSN 1614-7065, Vol. 36, nr 6, s. 491-494Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Revealing the charge generation is a crucial step to understand the organic photovoltaics. Recent development in non-fullerene organic solar cells (OSCs) indicates efficient charge separation even with negligible energetic offset between the donor and acceptor materials. These new findings trigger a critical question concerning the charge separation mechanism in OSCs, traditionally believed to result from sufficient energetic offset between the polymer donor and fullerene acceptor. We propose a new mechanism, which involves the molecular electrostatic potential, to explain efficient charge separation in non-fullerene OSCs. Together with the new mechanism, we demonstrate a record efficiency of similar to 12% for systems with negligible energetic offset between donor and acceptor materials. Our analysis also rationalizes different requirement of the energetic offset between fullerene-based and non-fullerene OSCs, and paves the way for further design of OSC materials with both high photocurrent and high photovoltage at the same time.

  • 646.
    Yin, Bin
    et al.
    Tianjin University of Technology.
    Yang, Liying
    Tianjin University of Technology.
    Liu, Yongsheng
    Nankai University.
    Chen, Yongsheng
    Nankai University.
    Qi, Qingjin
    Tianjin University of Technology.
    Zhang, Fengling
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Yin, Shougen
    Tianjin University of Technology.
    Solution-processed bulk heterojunction organic solar cells based on an oligothiophene derivative2010Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 97, nr 2, s. 023303-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organic bulk heterojunction (BHJ) solar cells based on a dicyanovinyl-substituted oligothiophene as a donor and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as an acceptor were fabricated and characterized. The oligothiophene derivative can absorb long wavelength photons of the solar radiation, which makes the solar cells with an optimized weight ratio of 1:1.4 have a decent short-circuit current density (12.4 mA/cm(2)) and open-circuit voltage (0.88 V) under AM 1.5G illumination with an intensity of 100 mW/cm(2). A power conversion efficiency (PCE) of 3.7% is achieved, which is among the best PCEs of solution processed small molecule BHJ solar cells.

  • 647.
    Yohannes, T.
    et al.
    Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
    Zhang, Fengling
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Svensson, M.
    Department of Organic Chemistry, Chalmers University of Technology, Göteborg S-41296, Sweden.
    Hummelen, J.C.
    Stratingh Institute, University of Groningen, Nijenborgh 4, Groningen 9747 AG, Netherlands.
    Andersson, M.R.
    Department of Organic Chemistry, Chalmers University of Technology, Göteborg S-41296, Sweden.
    Inganäs, Olle
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik.
    Polyfluorene copolymer based bulk heterojunction solar cells2004Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 449, nr 1-2, s. 152-157Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bulk heterojunction solar cells based on blends of photoactive layers of polyfluorene copolymer Poly((2,7-(9-(2'-ethylhexyl)-9-hexyl-fluorene)-alt-5,5-(4', 7'-di-2-thienyl-2',1',3'-benzothiadiazole))-co-(2, 7-(9-(2'-ethylhexyl)-9-hexyl-fluorene)-alt-2,5-thiophene)) (LBPF3) acting as electron donor, and [6,6]-phenyl-C61-butyric acid methylester (PCBM), acting as electron acceptor, were constructed and studied. The power conversion efficiency for a 1:4 (by weight) blend of LBPF3:PCBM under simulated solar light illumination having light intensity of 100 mW/cm2 was 1.7%, and 9.2% under monochromatic (565 nm) light illumination with light intensity of 0.145 mW/cm2. The maximum external quantum efficiency (incident photons to converted electrons) for this device was found to be above 40% from 400 to 560 nm. The effects of blend composition and film thickness on the photovoltaic parameters were also studied. The incident light intensity dependence of the short circuit current showed a linear relationship. © 2003 Elsevier B.V. All rights reserved.

  • 648.
    Yu, Hongling
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Wang, Heyong
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Zhang, Jiangbin
    Univ Cambridge, England; Imperial Coll London, England.
    Lu, Jun
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Yuan, Zhongcheng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Xu, Weidong
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Nanjing Tech Univ, Peoples R China.
    Hultman, Lars
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Bakulin, Artem A.
    Imperial Coll London, England.
    Friend, Richard H.
    Univ Cambridge, England.
    Wang, Jianpu
    Nanjing Tech Univ, Peoples R China.
    Liu, Xiaoke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten. Univ Cambridge, England.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Efficient and Tunable Electroluminescence from In Situ Synthesized Perovskite Quantum Dots2019Ingår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 15, nr 8, artikel-id 1804947Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Semiconductor quantum dots (QDs) are among the most promising next-generation optoelectronic materials. QDs are generally obtained through either epitaxial or colloidal growth and carry the promise for solution-processed high-performance optoelectronic devices such as light-emitting diodes (LEDs), solar cells, etc. Herein, a straightforward approach to synthesize perovskite QDs and demonstrate their applications in efficient LEDs is reported. The perovskite QDs with controllable crystal sizes and properties are in situ synthesized through one-step spin-coating from perovskite precursor solutions followed by thermal annealing. These perovskite QDs feature size-dependent quantum confinement effect (with readily tunable emissions) and radiative monomolecular recombination. Despite the substantial structural inhomogeneity, the in situ generated perovskite QDs films emit narrow-bandwidth emission and high color stability due to efficient energy transfer between nanostructures that sweeps away the unfavorable disorder effects. Based on these materials, efficient LEDs with external quantum efficiencies up to 11.0% are realized. This makes the technologically appealing in situ approach promising for further development of state-of-the-art LED systems and other optoelectronic devices.

    Publikationen är tillgänglig i fulltext från 2020-01-28 13:23
  • 649.
    Yu, Liyang
    et al.
    Sichuan Univ, Peoples R China; Chalmers Univ Technol, Sweden.
    Qian, Deping
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Marina, Sara
    Univ Basque Country, Spain; Univ Basque Country, Spain.
    Nugroho, Ferry A. A.
    Chalmers Univ Technol, Sweden.
    Sharma, Anirudh
    Flinders Univ S Australia, Australia; Univ Bordeaux, France.
    Hultmark, Sandra
    Chalmers Univ Technol, Sweden.
    Hofmann, Anna I.
    Chalmers Univ Technol, Sweden.
    Kroon, Renee
    Chalmers Univ Technol, Sweden.
    Benduhn, Johannes
    Tech Univ Dresden, Germany; Tech Univ Dresden, Germany.
    Smilgies, Detlef-M.
    CHESS, NY 14850 USA.
    Vandewal, Koen
    Hasselt Univ, Belgium.
    Andersson, Mats R.
    Flinders Univ S Australia, Australia.
    Langhammer, Christoph
    Chalmers Univ Technol, Sweden.
    Martin, Jaime
    Univ Basque Country, Spain; Univ Basque Country, Spain; Ikerbasque, Spain.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Mueller, Christian
    Chalmers Univ Technol, Sweden.
    Diffusion-Limited Crystallization: A Rationale for the Thermal Stability of Non-Fullerene Solar Cells2019Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, nr 24, s. 21766-21774Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Organic solar cells are thought to suffer from poor thermal stability of the active layer nanostructure, a common belief that is based on the extensive work that has been carried out on fullerene-based systems. We show that a widely studied non-fullerene acceptor, the indacenodithienothiophene-based acceptor ITIC, crystallizes in a profoundly different way as compared to fullerenes. Although fullerenes are frozen below the glass-transition temperature T-g of the photovoltaic blend, ITIC can undergo a glass-crystal transition considerably below its high T-g of similar to 180 degrees C. Nanoscopic crystallites of a low-temperature polymorph are able to form through a diffusion-limited crystallization process. The resulting fine-grained nanostructure does not evolve further with time and hence is characterized by a high degree of thermal stability. Instead, above T-g, the low temperature polymorph melts, and micrometer-sized crystals of a high-temperature polymorph develop, enabled by more rapid diffusion and hence long-range mass transport. This leads to the same detrimental decrease in photovoltaic performance that is known to occur also in the case of fullerene-based blends. Besides explaining the superior thermal stability of non-fullerene blends at relatively high temperatures, our work introduces a new rationale for the design of bulk heterojunctions that is not based on the selection of high-T-g materials per se but diffusion-limited crystallization. The planar structure of ITIC and potentially other non-fullerene acceptors readily facilitates the desired glass-crystal transition, which constitutes a significant advantage over fullerenes, and may pave the way for truly stable organic solar cells.

  • 650.
    Yuan, F.
    et al.
    Nanjing University, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska högskolan.
    Wang, K. F.
    Nanjing University, Peoples R China.
    Dong, S.
    Nanjing University, Peoples R China.
    Wang, Y.
    Nanjing University, Peoples R China.
    Liu, J. -M.
    Nanjing University, Peoples R China.
    Effect of Pr doping on ferroelectric behaviors of Pb(Zr0.65Ti0.35)O-32008Ingår i: International Journal of Modern Physics B, ISSN 0217-9792, Vol. 22, nr 13, s. 2070-2081Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pr-doped Pb(Zr0.65Ti0.35)O-3 (Pb1-xPr (Zr0.65Ti0.35)(1-x)/O-4(3), PPZT) ceramic samples are prepared using conventional solid-state sintering method, and their structural, dielectric, ferroelectric, and piezoelectric properties are investigated, focusing on the effects of Pr-doping. Upon increasing Pr doping level x, a transition of the crystallographic structure from rhombohedral symmetry to tetrahedral and finally to pseudocubic symmetry is observed at x similar to 0.08. The detailed dielectric measurements present a clear indication of relaxor-like behaviors at x = 0.08, while the samples at x less than 0.08 offer slightly improved ferroelectric properties compared with pure Pb(Zr0.65Ti0.35)O-3. In spite of the dielectric relaxor behaviors induced by Pr-doping, both the ferroelectric and piezoelectric properties of PPZT are degraded at x = 0.08. The physics underlying the Pr-doping induced relaxor behaviors is then discussed.

101112131415 601 - 650 av 720
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf