Construction of Bi2S3-BiOBr nanosheets on TiO2 NTA as the effective photocatalysts: Pollutant removal, photoelectric conversion and hydrogen generation.

Novel energy material is the investigation focus to overcome the environment pollution and resource shortage crisis. TiO2 nanotube arrays (TiO2 NTA) could be used for pollutant decomposition, photoelectric conversion and H2, CH4 generation. BiOBr nanosheets were fabricated on TiO2 NTA by a solvothermal deposition method, and then transformed into Bi2S3 nanosheets after the ion exchange reaction. The results revealed that the ion concentration significantly influenced the morphology, microstructure, optical harvesting and photoelectrochemical capacity of Bi2S3-BiOBr/TiO2 NTA. The samples also exhibited high photocatalytic activity for the removal of dyes and Cr(VI), and the excellent photocurrent and photovoltage were obtained under visible light irradiation. The photocatalytic water splitting for hydrogen generation was carried out, and the photocatalytic hydrogen production rate achieved 17.26 μmol·cm-2·h-1. The photocatalyst showed the remarkable stability, and the photocatalytic ability still maintained high level after several repeated photocatalytic cycles. The photocatalytic data indicated that the Bi2S3-BiOBr/TiO2 NTA photocatalyst provided a perfect strategy for the sensitizer deposition on TiO2 NTA and novel approach for the photocatalytic performance improvement.