Probing the edge-related properties of atomically thin MoS2 at nanoscale

Teng-Xiang Huang; Xin Cong; Si-Si Wu; Kai-Qiang Lin; Xu Yao; Yu-Han He; Jiang-Bin Wu; Yi-Fan Bao; Sheng-Chao Huang; Xiang Wang; Ping-Heng Tan; Bin Ren

doi:10.1038/s41467-019-13486-7

Probing the edge-related properties of atomically thin MoS₂ at nanoscale

Nat Commun. 2019 Dec 5;10(1):5544. doi: 10.1038/s41467-019-13486-7.

Authors

Teng-Xiang Huang¹, Xin Cong^{2

3}, Si-Si Wu¹, Kai-Qiang Lin¹, Xu Yao¹, Yu-Han He¹, Jiang-Bin Wu², Yi-Fan Bao¹, Sheng-Chao Huang¹, Xiang Wang⁴, Ping-Heng Tan^{5

6}, Bin Ren⁷

Affiliations

¹ State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
² State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China.
³ Center of Materials Science and Optoelectronics Engineering & CAS Center of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, 100049, China.
⁴ State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China. wangxiang@xmu.edu.cn.
⁵ State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China. phtan@semi.ac.cn.
⁶ Center of Materials Science and Optoelectronics Engineering & CAS Center of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, 100049, China. phtan@semi.ac.cn.
⁷ State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China. bren@xmu.edu.cn.

Abstract

Defects can induce drastic changes of the electronic properties of two-dimensional transition metal dichalcogenides and influence their applications. It is still a great challenge to characterize small defects and correlate their structures with properties. Here, we show that tip-enhanced Raman spectroscopy (TERS) can obtain distinctly different Raman features of edge defects in atomically thin MoS₂, which allows us to probe their unique electronic properties and identify defect types (e.g., armchair and zigzag edges) in ambient. We observed an edge-induced Raman peak (396 cm^-1) activated by the double resonance Raman scattering (DRRS) process and revealed electron-phonon interaction in edges. We further visualize the edge-induced band bending region by using this DRRS peak and electronic transition region using the electron density-sensitive Raman peak at 406 cm^-1. The power of TERS demonstrated in MoS₂ can also be extended to other 2D materials, which may guide the defect engineering for desired properties.

Publication types

Research Support, Non-U.S. Gov't