Modulating electron density of vacancy site by single Au atom for effective CO2 photoreduction

Yuehan Cao; Lan Guo; Meng Dan; Dmitry E Doronkin; Chunqiu Han; Zhiqiang Rao; Yang Liu; Jie Meng; Zeai Huang; Kaibo Zheng; Peng Chen; Fan Dong; Ying Zhou

doi:10.1038/s41467-021-21925-7

Modulating electron density of vacancy site by single Au atom for effective CO₂ photoreduction

Nat Commun. 2021 Mar 15;12(1):1675. doi: 10.1038/s41467-021-21925-7.

Authors

Yuehan Cao^#^{1

2}, Lan Guo^#², Meng Dan^{2

3}, Dmitry E Doronkin⁴, Chunqiu Han², Zhiqiang Rao², Yang Liu^{2

3}, Jie Meng^{3

5}, Zeai Huang², Kaibo Zheng^{3

5}, Peng Chen^{2

6}, Fan Dong⁶, Ying Zhou^{7

8}

Affiliations

¹ State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, China.
² The Center of New Energy Materials and Technology, School of New Energy and Materials, Southwest Petroleum University, Chengdu, China.
³ The Division of Chemical Physics and Nano-Lund, Lund University, Lund, Sweden.
⁴ Institute for Chemical Technology and Polymer Chemistry and Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany.
⁵ Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Denmark.
⁶ Research Center for Environmental Science and Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, China.
⁷ State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, China. yzhou@swpu.edu.cn.
⁸ The Center of New Energy Materials and Technology, School of New Energy and Materials, Southwest Petroleum University, Chengdu, China. yzhou@swpu.edu.cn.

^# Contributed equally.

Abstract

The surface electron density significantly affects the photocatalytic efficiency, especially the photocatalytic CO₂ reduction reaction, which involves multi-electron participation in the conversion process. Herein, we propose a conceptually different mechanism for surface electron density modulation based on the model of Au anchored CdS. We firstly manipulate the direction of electron transfer by regulating the vacancy types of CdS. When electrons accumulate on vacancies instead of single Au atoms, the adsorption types of CO₂ change from physical adsorption to chemical adsorption. More importantly, the surface electron density is manipulated by controlling the size of Au nanostructures. When Au nanoclusters downsize to single Au atoms, the strong hybridization of Au 5d and S 2p orbits accelerates the photo-electrons transfer onto the surface, resulting in more electrons available for CO₂ reduction. As a result, the product generation rate of Au_SA/Cd_1-xS manifests a remarkable at least 113-fold enhancement compared with pristine Cd_1-xS.