Salt-Assisted Selective Growth of H-phase Monolayer VSe2 with Apparent Hole Transport Behavior

Jiawen You; Jie Pan; Shun-Li Shang; Xiang Xu; Zhenjing Liu; Jingwei Li; Hongwei Liu; Ting Kang; Mengyang Xu; Shaobo Li; Deqi Kong; Wenliang Wang; Zhaoli Gao; Xing Zhou; Tianyou Zhai; Zi-Kui Liu; Jang-Kyo Kim; Zhengtang Luo

doi:10.1021/acs.nanolett.2c04133

Salt-Assisted Selective Growth of H-phase Monolayer VSe₂ with Apparent Hole Transport Behavior

Nano Lett. 2022 Dec 28;22(24):10167-10175. doi: 10.1021/acs.nanolett.2c04133. Epub 2022 Dec 7.

Authors

Jiawen You¹, Jie Pan², Shun-Li Shang³, Xiang Xu⁴, Zhenjing Liu¹, Jingwei Li¹, Hongwei Liu¹, Ting Kang¹, Mengyang Xu¹, Shaobo Li^{1

5}, Deqi Kong⁵, Wenliang Wang^{1

5}, Zhaoli Gao^{6

7}, Xing Zhou⁴, Tianyou Zhai⁴, Zi-Kui Liu³, Jang-Kyo Kim⁸, Zhengtang Luo^{1

9}

Affiliations

¹ Department of Chemical and Biological Engineering, Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology, William Mong Institute of Nano Science and Technology and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong999777, P. R. China.
² Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong999777, P. R. China.
³ Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania16802, United States.
⁴ School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan430074, P. R. China.
⁵ State Key Laboratory of Luminescent Materials and Devices, Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640, P. R. China.
⁶ Department of Biomedical Engineering, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong999777, P. R. China.
⁷ CUHK Shenzhen Research Institute, No.10, second, Yuexing Road, Nanshan, Shenzhen518057, P. R. China.
⁸ Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong999777, P. R. China.
⁹ The Hong Kong University of Science and Technology Shenzhen Research Institute, No. 9 Yuexing first RD, South Area Hi-tech Park, Nanshan, Shenzhen518057, China.

PMID: 36475688
DOI: 10.1021/acs.nanolett.2c04133

Abstract

Vanadium diselenide (VSe₂) exhibits versatile electronic and magnetic properties in the trigonal prismatic (H-) and octahedral (T-) phases. Compared to the metallic T-phase, the H-phase with a tunable semiconductor property is predicted to be a ferrovalley material with spontaneous valley polarization. Herein we report an epitaxial growth of the monolayer 2D VSe₂ on a mica substrate via the chemical vapor deposition (CVD) method by introducing salt in the precursor. Our first-principles calculations suggest that the monolayer H-phase VSe₂ with a large lateral size is thermodynamically favorable. The honeycomb-like structure and the broken symmetry are directly observed by spherical aberration-corrected scanning transmission electron microscopy (STEM) and confirmed by giant second harmonic generation (SHG) intensity. The p-type transport behavior is further evidenced by the temperature-dependent resistance and field-effect device study. The present work introduces a new phase-stable 2D transition metal dichalcogenide, opening the prospect of novel electronic and spintronics device design.

Keywords: 2D semiconductor; Chemical vapor deposition; Phase-selective growth; VSe2.