Property Tuning of Two-Dimensional Materials by Stacking Order and applications of homostructural devices

ORAL

Abstract

The optical and electronic structures of two-dimensional (2D) materials often show very strong layer-dependent properties. Such properties allow us to achieve various functionalities using different thickness (layer number), stacking order and heterostructures. The stacking-dependent properties allow us to build optoelectronic devices using the same material and same thickness, but it is a much less explored topic. Detailed understanding of the inter-layer interaction via stacking order will help greatly in tailoring the properties of 2D materials for applications, e.g. in pn junction, transistors, solar cells and LEDs.

In this talk, we use ultra-low wavenumber Raman and PL techniques and electric measurements, as well as simulation to study 2- & 3-layer 2D MoS2. The Raman and PL spectra also show clear correlation with layer-thickness and stacking sequence. We fabricated homostructured devices using differently stacked 2-layer MoS2. Photocurrent measurements and ab initio calculations reveal that difference in the electronic structures mainly arises from competition between spin-orbit coupling and interlayer coupling in different structural configurations.

*The work is supported by MOE Singapore: AcRF RG156/19; RG57/21; MOE-T2EP50220-0020; MOE2016-T3-1-006 (S).

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Publication: 1. Juan Xia, Jiaxu Yan, Zenghui Wang, Yongmin He, Yongji Gong, Weiqiang Chen, Tze Chien Sum, Zheng Liu, Pulickel M. Ajayan & Zexiang Shen, Strong coupling and pressure engineering in WSe2–MoSe2 heterobilayers, Nature Physics, 17, 92–98 (2021).
2. Q.D. Fu, X.W. Wang, J.D. Zhou, J. Xia, Q.S. Zeng, D.H. Lv, C. Zhu, X.L. Wang, Y. Shen, X.M. Li, Y.N. Hua, F.C. Liu, Z.X. Shen, C.H. Jin, Z. Liu, One-Step Synthesis of Metal/Semiconductor Heterostructure NbS2/MoS2, Chemistry of Materials, 30 (2018) 4001-4007.
3. J.D. Zhou, F.C. Liu, J.H. Lin, X.W. Huang, J. Xia, B.W. Zhang, Q.S. Zeng, H. Wang, C. Zhu, L. Niu, X.W. Wang, W. Fu, P. Yu, T.R. Chang, C.H. Hsu, D. Wu, H.T. Jeng, Y.Z. Huang, H. Lin, Z.X. Shen, C.L. Yang, L. Lu, K. Suenaga, W. Zhou, S.T. Pantelides, G.T. Liu, Z. Liu, Large-Area and High-Quality 2D Transition Metal Telluride, Advanced materials, 29 (2017).
4. J. Xia, Q.S. Zeng, J.D. Zhou, W. Zhou, Q. Zhang, J.X. Yan, Z. Liu, Z.X. Shen, Current rectification and asymmetric photoresponse in MoS2 stacking-induced homojunctions, 2D Materials, 4 (2017).
5. J. Xia, J.X. Yan, Z.X. Shen, Transition metal dichalcogenides: structural, optical and electronic property tuning via thickness and stacking, Flatchem, 4 (2017) 1-19.
6. J. Xia, X.L. Wang, B.K. Tay, S.S. Chen, Z. Liu, J.X. Yan, Z.X. Shen, Valley polarization in stacked MoS2 induced by circularly polarized light, Nano Research, 10 (2017) 1618-1626
7. J. Xia, D.F. Li, J.D. Zhou, P. Yu, J.H. Lin, J.L. Kuo, H.B. Li, Z. Liu, J.X. Yan, Z.X. Shen, Pressure Induced Phase Transition in Weyl Semimetallic WTe2, Small, 13 (2017).
8. J.X. Yan, J. Xia, X.L. Wang, L. Liu, J.L. Kuo, B.K. Tay, S.S. Chen, W. Zhou, Z. Liu, Z.X. Shen, Stacking-Dependent Interlayer Coupling in Trilayer Mo52 with Broken Inversion Symmetry, Nano letters, 15 (2015) 8155-8161.

Presenters

  • zexiang shen

    • Centre for Disruptive Photonic Technologies, Nanyang Technological University, 637371, Singapore.
    • Nanyang Technological University

Authors

  • zexiang shen

    • Centre for Disruptive Photonic Technologies, Nanyang Technological University, 637371, Singapore.
    • Nanyang Technological University

  • Juan Xia

    • University of Electronic Science and Technology of China

  • Jiaxu Yan

    • Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM), Nanji
    • Nanjing Tech University