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Qu Q, Liu B, Liu H, Liang J, Wang J, Pan D, Sou IK. Role of topological surface states and mirror symmetry in topological crystalline insulator SnTe as an efficient electrocatalyst. NANOSCALE 2021; 13:18160-18172. [PMID: 34704582 DOI: 10.1039/d1nr05089c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The surface orientation dependence on the hydrogen evolution reaction (HER) performance of topological crystalline insulator (TCI) SnTe thin films is studied. Their intrinsic activities are determined by linear sweep voltammetry and cyclic voltammetry measurements. It is found that SnTe (001) and (111) surfaces exhibit intrinsic activities significantly larger than the (211) surface. Density functional theory calculations reveal that pure (001) and (111) surfaces are not good electrocatalysts, while those with Sn vacancies or partially oxidized surfaces, with the latter as evidenced by X-ray photoelectron spectroscopy, have high activity. The calculated overall performance of the (001) and (111) surfaces with robust topological surface states (TSSs) is better than that of the lowly symmetric (211) surface with fragile or without TSSs, which is further supported by their measured weak antilocalization strength. The high HER activity of SnTe (001) and (111) is attributed to the enhanced charge transfer between H atoms and TSSs. We also address the effect of possible surface facets and the contrast of the HER activity of the available active sites among the three samples. Our study demonstrates that the TSSs and mirror symmetry of TCIs expedite their HER activity.
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Affiliation(s)
- Qing Qu
- Nano Science and Technology Program, The Hong Kong University of Science and Technology, Hong Kong, China.
- William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Bin Liu
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
| | - Hongtao Liu
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
| | - Jing Liang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Jiannong Wang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Ding Pan
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Iam Keong Sou
- Nano Science and Technology Program, The Hong Kong University of Science and Technology, Hong Kong, China.
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Hong Kong, China
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