Research
Phase Engineering of Two-Dimensional Materials
Two-dimensional atomic crystals such as transition metal dichalcogenides (TMDs) have recently attracted renewed interests because their intriguing quantum phases related with lattice distortion, spin interaction, and dimensional crossover such as charge density waves (CDWs) and 2D magnetism. However, the combined effect of many factors in TMDs, such as spin–orbit, electron–phonon, and electron–electron interactions, stabilizes a single quantum phase at a given temperature and pressure, which restricts original device operations with various quantum phases. We study nontrivial polymorphic quantum states, CDW phases, are reported in TMDs at room temperature, which is unique among various CDW systems; the doping concentration determines the formation of CDW phases in TMDs at ambient conditions.
Related Papers
[1] S. Cho et al. Phase Patterning for Ohmic Homojunction Contact in MoTe2, Science, 349 (6248), 625 (2015)
[2] D. H. Keum et al. Bandgap opening in few-layered monoclinic MoTe2, Nature Physics, 11, 482-486 (2015)
[3] D. Won et al. Polymorphic spin, charge, and lattice waves in vanadium ditelluride, Advanced Materials, 2020, 1906578 (2020)
Basal-Plane Catalytic Activity of Layered Metallic Transition Metal Ditellurides
The electrochemical hydrogen evolution reaction (HER) of two-dimensional metallic transition metal dichalcogenides, TMTe2 (TM: Mo, W, and V) was studied. We found that TMTe2 acts as a HER-active catalyst due to the inherent catalytic activity of its basal plane.
Related Papers
[1] J. Seok et al. Active hydrogen evolution through lattice distortion in metallic MoTe2, 2D Materials, 4, 025061 (2017)
[2] H. Kwon et al. Basal-Plane Catalytic Activity of Layered Metallic Transition Metal Ditellurides for Hydrogen Evolution Reaction, Applied Sciences, 10(9), 3087 (2020)
[3] J. H. Kim et al. Efficient hydrogen evolution reaction at the phase transition boundary of polymorphic Mo1-xWxTe2, APL Materials, 10, 061107 (2022)