Electrical and optoelectronic anisotropy and surface electron accumulation in ReS 2 nanostructures.

Autor: Bangolla HK; Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan. rsc@mail.ntust.edu.tw., Yusuf Fakhri M; Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan. rsc@mail.ntust.edu.tw., Lin CH; Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan. rsc@mail.ntust.edu.tw., Cheng CM; National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan.; Department of Physics, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.; Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan.; Taiwan Consortium of Emergent Crystalline Materials, National Science and Technology Council, Taipei 10601, Taiwan., Lu YH; Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan., Fu TY; Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan., Selvarasu P; Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan. rsc@mail.ntust.edu.tw., Ulaganathan RK; Institute of Physics, Academia Sinica, Taipei 115201, Taiwan., Sankar R; Institute of Physics, Academia Sinica, Taipei 115201, Taiwan., Chen RS; Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan. rsc@mail.ntust.edu.tw.
Jazyk: angličtina
Zdroj: Nanoscale [Nanoscale] 2023 Dec 14; Vol. 15 (48), pp. 19735-19745. Date of Electronic Publication: 2023 Dec 14.
DOI: 10.1039/d3nr04830f
Abstrakt: Two interesting electronic transport properties including in-plane anisotropy and nonhomogeneous carrier distribution were observed in ReS 2 nanoflakes. The electrical conductivity defined by the current parallel to the b -axis (‖ b ) is 32 times higher than that perpendicular to the b -axis (⊥ b ). Similar anisotropy was also observed in optoelectronic properties in which the ratio of responsivity ‖ b to ⊥ b reaches 20. In addition, conductivity and thermal activation energy with substantial thickness dependence were observed, which indicates a surface-dominant 2D transport in ReS 2 nanoflakes. The presence of surface electron accumulation (SEA) in ReS 2 has been confirmed by angle-resolved photoemission spectroscopy and scanning tunneling spectroscopy. The electron concentration (∼10 19 cm -3 ) at the surface is over three orders of magnitude higher than that of the bulks. Sulfur vacancies which are sensitive to air molecules are suggested to be the major factor resulting in SEA and high conductivity in ReS 2 nanostructures.
Databáze: MEDLINE
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