2D/2D Bi2MoO6/g-C3N4 S-scheme heterojunction photocatalyst with enhanced visible-light activity by Au loading

By Qiaoqiao Li, Wenli Zhao, Zicheng Zhai, Kaixu Ren, Ting Wang, H. Guan, Haifeng Shi. 2020

208 citations recorded by the source corpus.

Abstract A novel 2D/2D Bi2MoO6/g-C3N4 step-scheme (S-scheme) composite by loading Au as cocatalyst was successfully fabricated using a photoreduction and hydrothermal route. The obtained Bi2MoO6/g-C3N4/Au photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photo-electron spectroscopy (XPS), UV-vis diffuse reflectance spectra (UV-vis), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL), photocurrent response(I-t), and electrochemical impedance spectroscopy (EIS). The HRTEM images revealed that an intimate interface in composites were formed. The optimum photocatalytic activity of Rhodamine B degradation over Bi2MoO6/g-C3N4/Au was about 9.7 times and 13.1 times as high as those of Bi2MoO6 and g-C3N4, respectively. The notably improved photocatalytic activity of Bi2MoO6/g-C3N4/Au could be mainly ascribed to the abundant active sites and the enhanced separation efficiency of photogenerated carriers in Bi2MoO6/g-C3N4 S-scheme system. Notably, Au nanoparticles could act as a co-catalyst to further promote electron transfer and separation from the conduction band of g-C3N4. Additionally, a possible step-scheme photocatalytic reaction mechanism of RhB degradation over Bi2MoO6/g-C3N4/Au was tentatively proposed. PL and transient photocurrent analysis implied that Bi2MoO6/g-C3N4/Au photocatalysts possessed the lower recombination rate of photogenerated carriers compared with pure Bi2MoO6 and g-C3N4, respectively. The present work is expected to provide useful information in designing 2D/2D S-scheme heterojunction photocatalysts.

Subfields: Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/87e1aea5075bc11663870c59e04b498d36590210