Synergistic enhancing photoelectrochemical response of Bi10O6S9 with WO3 optical heterojunction in wide wavelength range

• Published in: Applied surface science 2020-04, Vol.509, p.144697, Article 144697
• Main Authors: Shi, Changchang, Zhou, Xiaowen, Li, Wanqing, Guo, Hongmei, Zhao, Yanjie, Ruan, Limin, Xu, Chao, Zeng, Wei, Liang, Dong
• Format: Article
• Language: English
• Subjects: Bismuth oxysulfide; Light-trapping nanostructure; Optical heterojunction; Tungsten trioxide
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.144697

[Display omitted] •The photoelectrochemical response of modified Bi10O6S9 is greatly improved.•The light-trapping and heterojunction features of WO3 are both utilized.•The electrode can effectively absorb lights even in long-wavelength range.•A simple and effective chemical bath deposition method is employed. Owing to the previously reported giant incident photon-to-current conversion efficiency of a bismuth oxysulfide nanofilm, an improved composite electrode is further developed in this work by in situ growing the bismuth oxysulfide nanosheets upon tungsten trioxide nanoplate, based on a simple chemical bath deposition method. A facile synergistic optical heterojunction structure is formed by coupling the multi-dimensional interlaced heterojunctions with light-trapping structure. It is observed that the interfacial charge transfer in device is accelerated and the light absorption is enhanced even in long-wavelength range, improving the separation and transfer efficiency of photo-excited electron/hole pares. The photocurrent response of 1.16 mA cm−2 at −0.1 V (vs. saturated calomel electrode) is achieved, which is 21 times and 1.8 times higher than those of pure tungsten trioxide electrode and pure bismuth oxysulfide electrode, respectively. This unique optical heterojunction is effective and provides a potential application in general photoelectrochemical sensors.