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Halim, Joseph
Publications (9 of 9) Show all publications
Magnuson, M., Halim, J. & Näslund, L.-Å. (2018). Chemical bonding in carbide MXene nanosheets. Journal of Electron Spectroscopy and Related Phenomena, 224, 27-32
Open this publication in new window or tab >>Chemical bonding in carbide MXene nanosheets
2018 (English)In: Journal of Electron Spectroscopy and Related Phenomena, ISSN 0368-2048, E-ISSN 1873-2526, Vol. 224, p. 27-32Article in journal (Refereed) Published
Abstract [en]

tThe chemical bonding in the carbide core and the surface chemistry in a new group of transition-metalcarbides Tin+1Cn-Tx(n = 1,2) called MXenes have been investigated by surface-sensitive valence bandX-ray photoelectron spectroscopy. Changes in band structures of stacked nano sheets of different thick-nesses are analyzed in connection to known hybridization regions of TiC and TiO2that affect elastic andtransport properties. By employing high excitation energy, the photoelectron cross-section for the C 2s– Ti 3d hybridization region at the bottom of the valence band is enhanced. As shown in this work, theO 2p and F 2p bands strongly depend both on the bond lengths to the surface groups and the adsorptionsites. The effect of surface oxidation and Ar+sputtering on the electronic structure is also discussed.

Place, publisher, year, edition, pages
Elsevier, 2018
Keyword
MXene, 2D materials, Valence band, X-ray photoelecton spectroscopy, XPS, Chemical bonding, Termination species
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:liu:diva-145690 (URN)10.1016/j.elspec.2017.09.006 (DOI)000428825400006 ()2-s2.0-85030792688 (Scopus ID)
Available from: 2018-03-16 Created: 2018-03-16 Last updated: 2018-06-04Bibliographically approved
Palisaitis, J., Persson, I., Halim, J., Rosén, J. & Persson, P. O. Å. (2018). On the Structural Stability of MXene and the Role of Transition Metal Adatoms. Nanoscale
Open this publication in new window or tab >>On the Structural Stability of MXene and the Role of Transition Metal Adatoms
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2018 (English)In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372Article in journal (Refereed) Accepted
Abstract [en]

In the present communication, the atomic structure and coordination of surface adsorbed species on Nb2C MXene is investigated over time. In particular, the influence of the Nb adatoms on the structural stability and oxidation behavior of the MXene is addressed. This investigation is based on plan-view geometry observations of single Nb2C MXene sheets by a combination of atomic-resolution scanning transmission electron microscopy (STEM), electron energy loss spectroscopy (EELS) and STEM image simulations.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2018
Keyword
2D material; MXene; Scanning Transmission Electron Microscopy; Structural Stability; Adatoms
National Category
Chemical Sciences
Identifiers
urn:nbn:se:liu:diva-148143 (URN)10.1039/C8NR01986J (DOI)29870038 (PubMedID)
Note

Funding agencies:The authors acknowledge the Swedish Research Council for funding under grants no. 2016- 04412 and 642-2013-8020, the Knut and Alice Wallenberg’s Foundation for support of the electron microscopy laboratory in Linköping, a Fellowship grant and a project grant (KAW 2015.0043). The authors also acknowledge Swedish Foundation for Strategic Research (SSF) through the Research Infrastructure Fellow program no. RIF 14-0074. The authors finally acknowledge support from the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No 2009 00971

Available from: 2018-05-31 Created: 2018-05-31 Last updated: 2018-06-07Bibliographically approved
Miranda, A., Halim, J., Barsoum, M. W. & Lorke, A. (2016). Electronic properties of freestanding Ti3C2Tx MXene monolayers. Applied Physics Letters, 108(3), 033102-1-033102-4, Article ID 033102.
Open this publication in new window or tab >>Electronic properties of freestanding Ti3C2Tx MXene monolayers
2016 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 108, no 3, p. 033102-1-033102-4, article id 033102Article in journal (Refereed) Published
Abstract [en]

We report on the electrical characterization of single MXene Ti(3)C(2)Tx flakes ( where T is a surface termination) and demonstrate the metallic nature of their conductivities. We also show that the carrier density can be modulated by an external gate voltage. The density of free carriers is estimated to be 8 +/- 3 X 10(21) cm(-3) while their mobility is estimated to be 0.7 +/- 0.2 cm(2)/Vs. Electrical measurements, in the presence of a magnetic field, show a small, but clearly discernable, quadratic increase in conductance at 2.5 K. (C) 2016 AIP Publishing LLC.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2016
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-127457 (URN)10.1063/1.4939971 (DOI)000373055500039 ()
Note

Funding Agencies|Ceramics program of the Division of Materials Research of the National Science Foundation [DMR-1310245]

Available from: 2016-04-30 Created: 2016-04-26 Last updated: 2017-11-30Bibliographically approved
Ghidiu, M., Halim, J., Kota, S., Bish, D., Gogotsi, Y. & Barsourm, M. W. (2016). Ion-Exchange and Cation Solvation Reactions in Ti3C2 MXene. Chemistry of Materials, 28(10), 3507-3514
Open this publication in new window or tab >>Ion-Exchange and Cation Solvation Reactions in Ti3C2 MXene
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2016 (English)In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 28, no 10, p. 3507-3514Article in journal (Refereed) Published
Abstract [en]

Ti3C2 and other two-dimensional transition metal carbides known as MXenes are currently being explored for many applications involving intercalated ions, from electrochemical energy storage, to contaminant sorption from water, to selected ion sieving. We report here a systematic investigation of ion exchange in Ti3C2 MXene and its hydration/dehydration behavior. We have investigated the effects of the presence of LiCl during the chemical etching of the MAX phase Ti3AlC2 into MXene Ti3C2Tx (T stands for surface termination) and found that the resulting MXene has Li+ cations in the interlayer space. We successfully exchanged the Li+ cations with K+, Na+, Rb+, Mg2+, and Ca2+ (supported by X-ray photoelectron and energy-dispersive spectroscopy) and found that the exchanged material expands on the unit-cell level in response to changes in humidity, with the nature expansion dependent on the intercalated cation, similar to behavior of clay minerals; stepwise expansions of the basal spacing were observed, with changes consistent with the size of the H2O molecule. Thermogravimetric analysis of the dehydration behavior of these materials shows that the amounts of H2O contained at ambient humidity correlates simply with the hydration enthalpy of the intercalated cation, and that the diffusion of the exiting H2O proceeds with kinetics similar to clays. These results have implications for understanding, controlling, and exploiting structural changes and H2O sorption in MXene films and powders utilized in applications involving ions, such as electrochemical capacitors, sensors, reverse osmosis membranes, or contaminant sorbents.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2016
National Category
Physical Chemistry
Identifiers
urn:nbn:se:liu:diva-129673 (URN)10.1021/acs.chemmater.6b01275 (DOI)000376825700034 ()
Note

Funding Agencies|U.S. National Science Foundation [DMR-1310245]; National Science Foundation [283036-3304]; Swedish Research Council [621-2014-4890]; Swedish Foundation for Strategic Research through the Synergy Grant FUNCASE Functional Carbides for Advanced Surface Engineering; U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences

Available from: 2016-06-23 Created: 2016-06-23 Last updated: 2017-11-28
Ren, C. E., Zhao, M.-Q., Makaryan, T., Halim, J., Boota, M., Kota, S., . . . Gogotsi, Y. (2016). Porous Two-Dimensional Transition Metal Carbide (MXene) Flakes for High-Performance Li-Ion Storage. CHEMELECTROCHEM, 3(5), 689-693
Open this publication in new window or tab >>Porous Two-Dimensional Transition Metal Carbide (MXene) Flakes for High-Performance Li-Ion Storage
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2016 (English)In: CHEMELECTROCHEM, ISSN 2196-0216, Vol. 3, no 5, p. 689-693Article in journal (Refereed) Published
Abstract [en]

Herein we develop a chemical etching method to produce porous two-dimensional (2D) Ti3C2Tx MXenes at room temperature in aqueous solutions. The as-produced porous Ti3C2Tx (p-Ti3C2Tx) have larger specific surface areas and more open structures than their pristine counterparts, and can be fabricated into flexible films with, or without, the addition of carbon nanotubes (CNTs). The as-fabricated p-Ti3C2Tx/CNT films showed significantly improved lithium ion storage capabilities compared to pristine Ti3C2Tx based films, with a very high capacity of approximate to 1250 mAhg(-1) at 0.1 C, excellent cycling stability, and good rate performance (330 mAhg(-1) at 10 C). Using the same chemical etching method, we also made porous Nb2CTx and V2CTx MXenes. Therefore, this study provides a simple, yet effective, procedure to introduce pores into MXenes and possibly other 2D sheets that in turn, can enhance their electrochemical properties.

Place, publisher, year, edition, pages
WILEY-V C H VERLAG GMBH, 2016
Keyword
etching; Li-ion storage; MXene; partial oxidation; porous 2D materials
National Category
Materials Chemistry
Identifiers
urn:nbn:se:liu:diva-130670 (URN)10.1002/celc.201600059 (DOI)000379985500002 ()
Note

Funding Agencies|Chinese Scholarship Council (CSC); Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center - U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences; Honda Research Institute USA, Inc.

Available from: 2016-08-20 Created: 2016-08-19 Last updated: 2016-08-20
Halim, J., Kota, S., Lukatskaya, M. R., Naguib, M., Zhao, M.-Q., Ju Moon, E., . . . Barsoum, M. W. (2016). Synthesis and Characterization of 2D Molybdenum Carbide (MXene). Advanced Functional Materials, 26(18), 3118-3127
Open this publication in new window or tab >>Synthesis and Characterization of 2D Molybdenum Carbide (MXene)
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2016 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 26, no 18, p. 3118-3127Article in journal (Refereed) Published
Abstract [en]

Large scale synthesis and delamination of 2D Mo2CTx (where T is a surface termination group) has been achieved by selectively etching gallium from the recently discovered nanolaminated, ternary transition metal carbide Mo2Ga2C. Different synthesis and delamination routes result in different flake morphologies. The resistivity of free-standing Mo2CTx films increases by an order of magnitude as the temperature is reduced from 300 to 10 K, suggesting semiconductor-like behavior of this MXene, in contrast to Ti3C2Tx which exhibits metallic behavior. At 10 K, the magnetoresistance is positive. Additionally, changes in electronic transport are observed upon annealing of the films. When 2 mu m thick films are tested as electrodes in supercapacitors, capacitances as high as 700 F cm(-3) in a 1 M sulfuric acid electrolyte and high capacity retention for at least 10,000 cycles at 10 A g(-1) are obtained. Free-standing Mo2CTx films, with approximate to 8 wt% carbon nanotubes, perform well when tested as an electrode material for Li-ions, especially at high rates. At 20 and 131 C cycling rates, stable reversible capacities of 250 and 76 mAh g(-1), respectively, are achieved for over 1000 cycles.

Place, publisher, year, edition, pages
WILEY-V C H VERLAG GMBH, 2016
National Category
Materials Chemistry
Identifiers
urn:nbn:se:liu:diva-130074 (URN)10.1002/adfm.201505328 (DOI)000377591500015 ()
Note

Funding Agencies|Swedish Research Council [621-2012-4430]; Swedish Foundation for Strategic Research through the Synergy Grant FUNCASE Functional Carbides for Advanced Surface Engineering; Laboratory Directed Research and Development Program of Oak Ridge National Laboratory; U.S. Army Research Office [W911NF-15-1-0133]

Available from: 2016-07-06 Created: 2016-07-06 Last updated: 2017-11-28
Lukatskaya, M. R., Halim, J., Dyatkin, B., Naguib, M., Buranova, Y. S., Barsoum, M. W. & Gogotsi, Y. (2014). Room-Temperature Carbide-Derived Carbon Synthesis by Electrochemical Etching of MAX Phases. Angewandte Chemie International Edition, 126(19), 4977-4980
Open this publication in new window or tab >>Room-Temperature Carbide-Derived Carbon Synthesis by Electrochemical Etching of MAX Phases
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2014 (English)In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 126, no 19, p. 4977-4980Article in journal (Refereed) Published
Abstract [en]

Porous carbons are widely used in energy storage and gas separation applications, but their synthesis always involves high temperatures. Herein we electrochemically selectively extract, at ambient temperature, the metal atoms from the ternary layered carbides, Ti3AlC2, Ti2AlC and Ti3SiC2 (MAX phases). The result is a predominantly amorphous carbide-derived carbon, with a narrow distribution of micropores. The latter is produced by placing the carbides in HF, HCl or NaCl solutions and applying anodic potentials. The pores that form when Ti3AlC2 is etched in dilute HF are around 0.5 nm in diameter. This approach forgoes energy-intensive thermal treatments and presents a novel method for developing carbons with finely tuned pores for a variety of applications, such as supercapacitor, battery electrodes or CO2 capture.

Place, publisher, year, edition, pages
John Wiley & Sons, 2014
Keyword
Carbide; Cyclovoltammetrie; Elektrochemie; Kohlenstoff; Oxidationen
National Category
Chemical Sciences Physical Chemistry
Identifiers
urn:nbn:se:liu:diva-111125 (URN)10.1002/ange.201402513 (DOI)
Available from: 2014-10-08 Created: 2014-10-08 Last updated: 2017-12-05Bibliographically approved
Halim, J. (2014). Synthesis and Characterization of 2D Nanocrystals and Thin Films of Transition Metal Carbides (MXenes). (Licentiate dissertation). Linköping: Linköping University Electronic Press
Open this publication in new window or tab >>Synthesis and Characterization of 2D Nanocrystals and Thin Films of Transition Metal Carbides (MXenes)
2014 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Two dimensional (2D) materials have received growing interest because of their unique properties compared to their bulk counterparts. Graphene is the archetype 2D solid, but other materials beyond graphene, such as MoS2 and BN have become potential candidates for several applications. Recently, a new family of 2D materials of early transition metal carbides and carbonitrides (Ti2CTx, Ti3C2Tx, Ti3CNTx, Ta4C3Tx, and more), labelled MXenes, has been discovered, where T stands for the surface-terminating groups.

Before the present work, MXenes had only been synthesized in the form of exfoliated and delaminated powders, which is not suitable for electronic applications. In this thesis, I demonstrate the synthesis of MXenes as epitaxial thin films, a more suitable form for electronic and photonic applications. Results show that 2D epitaxial Ti3C2Tx films - produced by HF and NH4HF2 etching of magnetron sputter-grown Ti3AlC2 - exhibit metallic conductive behaviour down to 100 K and are 90% transparent to light in the visible-infrared range. The results from this work may open the door for MXenes as potential candidates for transparent conductive electrodes as well as in electronic, photonic and sensing applications.

MXenes have been shown to intercalate cations and molecules between their layers that in turn can alter the surface termination groups. There is therefore a need to study the surface chemistries of synthetized MXenes to be able to study the effect of intercalation as well as altering the surface termination groups on the electronic structure and chemical states of the elements present in MXene layers. X-ray Photoelectron Spectroscopy (XPS) in-depth characterization was used to investigate surface chemistries of Ti3C2Tx and Ti2CTx. This thesis includes the discussion of the effect of Ar+ sputtering and the number of layers on the surface chemistry of MXenes. This study serves as a baseline for chemical modification and tailoring of the surface chemistry groups to potential uses and applications.

New MXene phases, Nb2CTx and V2CTx, are shown in this thesis to be produced from HF chemical etching of Nb2AlC and V2AlC powders. Characterization of the produced MXenes was carried out using Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Transmission Electron Microscope (TEM) and XPS. Nb2CTx and V2CTx showed promising performance as electrodes for Li-ion batteries.

In this thesis, electrochemical etching was used in an attempt to produce 2D metal carbides (MXene) from their ternary metal carbides, Ti3SiC2, Ti3AlC2 and Ti2AlC MAX phases. MAX phases in the form of highly dense bulk produced by Hot Isostatic Press. Several etching solutions were used such as HF, NaCl and HCl. Unlike the HF chemical etching of MAX phases, which results in MXenes, the electrochemical etching resulted in Carbide Derived Carbon (CDC). Here, I show the characterization of the produced CDC using several techniques such as XRD, TEM, Raman spectroscopy, and XPS. Electrochemical characterization was performed in the form of cyclic voltammetry, which sheds light on the etching mechanism.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2014. p. 41
Series
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1679
National Category
Materials Chemistry Inorganic Chemistry
Identifiers
urn:nbn:se:liu:diva-111128 (URN)10.3384/lic.diva-111128 (DOI)978-91-7519-225-3 (ISBN)
Presentation
2014-10-24, Planck, Fysikhuset, Campus Valla, Linköpings universitet, Linköping, 10:15 (English)
Opponent
Supervisors
Note

The series name Linköping Studies in Science and Technology Licentiate Thesis in this publication is incorrect. Correct name is Linköping Studies in Science and Technology. Thesis.

Available from: 2014-10-08 Created: 2014-10-08 Last updated: 2016-08-31Bibliographically approved
Halim, J., Cook, K. M., Näslund, L.-Å., Magnuson, M., Hultman, L., Gogotsi, Y., . . . Barsoum, M. W. (2014). X-ray Photoelectron Spectroscopy Characterization of Two-Dimensional Titanium Metal Carbides (MXenes).
Open this publication in new window or tab >>X-ray Photoelectron Spectroscopy Characterization of Two-Dimensional Titanium Metal Carbides (MXenes)
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2014 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Herein, we report X-ray Photoelectron Spectroscopy (XPS) analysis for cold pressed exfoliated 2D nanocrystals of transition metal carbides, MXenes. MXenes are a recently discovered family of 2D materials produced by selective chemical etching of the A element from MAX phases which are ternary metal carbides and nitrides. The latter has the formula of Mn+1AXn, where M is an early transition metal, A is an A-group element, and X is C and/or N. This study is a comparison between two MXenes, Ti3C2Tx and Ti2CTx, where Tx stands for surface termination groups such as –O, –OH, and –F. Ti3C2Tx and Ti2CTx were prepared by immersion of Ti3AlC2 and Ti2AlC powders in 50% conc. HF. A thorough XPS analysis was performed through peak fitting of high resolution XPS spectra and valence band, VB, spectra analysis. The effect of Ar sputtering as well as the number of layers n was the primarily interest of this study. According to the peak fitting analysis, both phases contain the following species, Ti–C, C–C, Ti–F, Ti–O and Ti–OH resulting in the following chemical formulas: Ti3C2(OH)x(O)y(F)z and Ti2C(OH)x(O)y(F)z. Comparing the VB spectra with the DOS calculations show the valance band spectra is actually a mixture of MXene with various terminations of OH, O and F. Before Ar+ sputtering both phases show a large percentage of fluorinated-TiO2 which is due to MXene surface oxidation as well as CHx, C-O and COO groups arising from either surface contaminations or due to drying the etched powders in ethanol after washing the powder of the HF acid. According to the VB spectra, it is shown that the fluorinated TiO2 is actually a mixture of anatase and rutile. The number of layers, n, also plays a role; the lower n, the more the MXene is prone to oxidation.

National Category
Physical Chemistry Chemical Sciences
Identifiers
urn:nbn:se:liu:diva-111127 (URN)
Available from: 2014-10-08 Created: 2014-10-08 Last updated: 2018-06-04Bibliographically approved
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