Fabrication of Highly Textured 2D SnSe Layers with Tunable Electronic Properties for Hydrogen Evolution

Qianyu Zhou; Mengya Wang; Yong Li; Yanfang Liu; Yuanfu Chen; Qi Wu; Shifeng Wang

doi:10.3390/molecules26113319

Fabrication of Highly Textured 2D SnSe Layers with Tunable Electronic Properties for Hydrogen Evolution

Molecules. 2021 Jun 1;26(11):3319. doi: 10.3390/molecules26113319.

Authors

Qianyu Zhou^{1

2

3}, Mengya Wang^{1

2

3}, Yong Li^{1

2

3}, Yanfang Liu^{1

2

4}, Yuanfu Chen^{2

4}, Qi Wu^{1

2

3}, Shifeng Wang^{1

2

3}

Affiliations

¹ Department of Physics, and Innovation center of Materials for Energy and Environment Technologies, College of Science, Tibet University, Lhasa 850000, China.
² Institute of Oxygen Supply, Center of Tibetan Studies (Everest Research Institute), Tibet University, Lhasa 850000, China.
³ Key Laboratory of Cosmic Rays (Tibet University), Ministry of Education, Lhasa 850000, China.
⁴ School of Electronic Science and Engineering, and State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China.

Abstract

Hydrogen is regarded to be one of the most promising renewable and clean energy sources. Finding a highly efficient and cost-effective catalyst to generate hydrogen via water splitting has become a research hotspot. Two-dimensional materials with exotic structural and electronic properties have been considered as economical alternatives. In this work, 2D SnSe films with high quality of crystallinity were grown on a mica substrate via molecular beam epitaxy. The electronic property of the prepared SnSe thin films can be easily and accurately tuned in situ by three orders of magnitude through the controllable compensation of Sn atoms. The prepared film normally exhibited p-type conduction due to the deficiency of Sn in the film during its growth. First-principle calculations explained that Sn vacancies can introduce additional reactive sites for the hydrogen evolution reaction (HER) and enhance the HER performance by accelerating electron migration and promoting continuous hydrogen generation, which was mirrored by the reduced Gibbs free energy by a factor of 2.3 as compared with the pure SnSe film. The results pave the way for synthesized 2D SnSe thin films in the applications of hydrogen production.

Keywords: 2D materials; DFT calculations; SnSe; defect engineering; hydrogen evolution; water splitting.

Abstract

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