Construction of an all-solid-state artificial Z-scheme system consisting of Bi2WO6/Au/CdS nanostructure for photocatalytic CO2 reduction into renewable hydrocarbon fuel

Meng Wang; Qiutong Han; Liang Li; Lanqin Tang; Haijin Li; Yong Zhou; Zhigang Zou

doi:10.1088/1361-6528/aa6bb5

Construction of an all-solid-state artificial Z-scheme system consisting of Bi₂WO₆/Au/CdS nanostructure for photocatalytic CO₂ reduction into renewable hydrocarbon fuel

Nanotechnology. 2017 Jul 7;28(27):274002. doi: 10.1088/1361-6528/aa6bb5.

Authors

Meng Wang¹, Qiutong Han, Liang Li, Lanqin Tang, Haijin Li, Yong Zhou, Zhigang Zou

Affiliation

¹ National Laboratory of Solid State Microstructures, Department of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China. Jiangsu Key Laboratory for Nano Technology, Nanjing University, Nanjing 210093, People's Republic of China. Eco-materials and Renewable Energy Research Center (ERERC), Nanjing University, Nanjing 210093, People's Republic of China.

PMID: 28616938
DOI: 10.1088/1361-6528/aa6bb5

Abstract

An all-solid-state Bi₂WO₆/Au/CdS Z-scheme system was constructed for the photocatalytic reduction of CO₂ into methane in the presence of water vapor. This Z-scheme consists of ultrathin Bi₂WO₆ nanoplates and CdS nanoparticles as photocatalysts, and a Au nanoparticle as a solid electron mediator offering a high speed charge transfer channel and leading to more efficient spatial separation of electron-hole pairs. The photo-generated electrons from the conduction band (CB) of Bi₂WO₆ transfer to the Au, and then release to the valence band (VB) of CdS to recombine with the holes of CdS. It allows the electrons remaining in the CB of CdS and holes in the VB of Bi₂WO₆ to possess strong reduction and oxidation powers, respectively, leading the Bi₂WO₆/Au/CdS to exhibit high photocatalytic reduction of CO₂, relative to bare Bi₂WO₆, Bi₂WO₆/Au, and Bi₂WO₆/CdS. The depressed hole density on CdS also enhances the stability of the CdS against photocorrosion.