AuCu alloys deposited on titanium dioxide nanosheets for efficient photocatalytic hydrogen evolution

• Published in: International journal of hydrogen energy Vol. 43; no. 32; pp. 15155 - 15163
• Main Authors: Zeng, Dedong, Yang, Liming, Zhou, Panpan, Hu, Dongsheng, Xie, Yu, Li, Shiqi, Jiang, Liushan, Ling, Yun, Zhao, Jinsheng
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 09.08.2018
• Subjects: Au–Cu alloys; Heterojunction; Hydrogen evolution; Photocatalysis; TiO2 nanosheets; TiO2 nanosheets; Photocatalysis; Hydrogen evolution; Au–Cu alloys; Heterojunction
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2018.06.078

This work first reports AuCu alloys deposited on the surface of TiO2 nanosheets (TiNs) to form heterojunction. A simple deposition-precipitation method was used to construct a new type of AuCu/TiNs heterostructures through gradually depositing Au and Cu nanoparticles on TiNs. Such structures served the dual advantage of constructing a heterostructure which can improve visible light absorption, and the formation of a Schottky barrier between AuCu alloys (lower Fermi level) and TiNs (higher Fermi level) which can suppress the recombination of photo-generated charge carriers to improve the overall photocatalytic activity. The mass ratio of Au and Cu in the AuCu/TiNs heterostructures and the sequence and method of their deposition are found to be the important factors which affect the photocatalytic performance. When the mass ratio of Au to Cu was determined to be 1: 1, the AuCu/TiNs heterostructure exhibited the best photocatalytic performance for hydrogen production from water splitting (over 9 times than TiNs, 1.47 times than Au/TiNs, and 1.75 times than Cu/TiNs). [Display omitted] •AuCu alloys/TiNs was constructed by a simple deposition-precipitation method.•The optimal mass ratio of Au and Cu was determined.•The sequence and method of deposition was optimized.•The Schottky barrier suppresses the recombination of charge carriers.•The charge transfer and photocatalytic degradation mechanism was explored.