liu.seSearch for publications in DiVA
Endre søk
Begrens søket
1 - 2 of 2
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Dimitriev, Oleg
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten. V Lashkaryov Inst Semicond Phys, Ukraine.
    Kysil, Dmytro
    V Lashkaryov Inst Semicond Phys, Ukraine.
    Zaderko, Alexander
    Taras Shevchenko Natl Univ Kyiv, Ukraine.
    Isaieva, Oksana
    V Lashkaryov Inst Semicond Phys, Ukraine; Natl Univ Kyiv Mohyla Acad, Ukraine.
    Vasin, Andrii
    V Lashkaryov Inst Semicond Phys, Ukraine; Natl Tech Univ, Ukraine.
    Piryatinski, Yuri
    Inst Phys, Ukraine.
    Fahlman, Mats
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten.
    Nazarov, Alexei
    V Lashkaryov Inst Semicond Phys, Ukraine; Natl Tech Univ, Ukraine.
    Photoluminescence quantum yield of carbon dots: emission due to multiple centers versus excitonic emission2024Inngår i: Nanoscale Advances, E-ISSN 2516-0230Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Carbon dots (CDs) are recognized as promising fluorescent nanomaterials with bright emission and large variations of photoluminescence quantum yield (PLQY). However, there is still no unique approach for explanation of mechanisms and recipes for synthetic procedures/chemical composition of CDs responsible for the enhancement of PLQY. Here, we compare photophysical behavior and PLQY of two types of CDs synthesized by different routes, leading to the different extent of oxidation and composition. The first type of CDs represents a conjugated carbon system oxidized by F, N and O heteroatoms, whereas the second type represents a non-conjugated carbon system oxidized by oxygen. Photophysical data, photoemission spectroscopy and microscopy data yield the suggestion that in the first case, a structure with a distinct carbon core and highly oxidized electron-accepting shell is formed. This leads to the excitonic type non-tunable emission with single-exponent decay and high PLQY with a strong dependence on the solvent polarity, being as high as 93% in dioxane and as low as 30% in aqueous medium, but which is vulnerable to photobleaching. In the second case, the oxidized CDs do not indicate a clear core-shell structure and show poor solvatochromism, negligible photobleaching, low PLQY varying in the range of 0.7-2.3% depending on the solvent used, and tunable emission with multi-exponent decay, which can be described by the model of multiple emission centers acting through a clustering-triggered emission mechanism. The obtained results lead to a strategy that allows one to design carbon nanomaterials with principally different PLQYs that differ by orders of magnitude.

  • 2.
    Ivashchuk, Anatoliy V
    et al.
    Natl Tech Univ Ukraine, Ukraine.
    Dusheiko, Mykhailo G.
    Natl Tech Univ Ukraine, Ukraine.
    Roshchina, Nina M.
    NAS Ukraine, Ukraine.
    Smertenko, Petro S.
    NAS Ukraine, Ukraine.
    Dimitriev, Oleg
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten. NAS Ukraine, Ukraine.
    Liu, Xianjie
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten.
    Impact of molecular layer on emergent photovoltaic response in silicon unraveled by photoelectron spectroscopy2021Inngår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 544, artikkel-id 148807Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The large photovoltaic response from homogeneous silicon wafer obtained upon deposition of a molecular layer on its surface remained an unexplained phenomenon so far. Here, we show by X-ray and ultraviolet photo-electron spectroscopy that deposition of species containing acidic groups on the surface of n-type silicon with native silicon oxide overlayer always results in increased work function of the hybrid interface. This effect is shown to originate due to the surface band bending of the silicon crystal upward, which is accompanied by a negative surface dipole formed. This effect is assigned to protonation of the silicon oxide film by molecular acidic groups, which in turn facilitates accumulation of a mirror negative charge at the Si-SiO2 interface, thus increasing the depth of the depletion region and height of the Schottky barrier in the silicon semiconductor, respectively. Comparison of the work functions of the samples in the dark and under illumination confirms formation of a depletion region at the silicon surface upon molecular adsorption.

1 - 2 of 2
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf