Wedged ß-In2S3 sensitized TiO2 films for enhanced photoelectrochemical hydrogen generation

As a photocatalytic material, the photoelectrochemical (PEC) performance of TiO2 is severely restricted due to wide band gap and rapid recombination of photogenerated electrons and holes. In order to effectively improve the PEC performance of TiO2, ß-In2S3 photocatalysts with different morphologies are attached to TiO2 film by hydrothermal method. Compared with other TiO2/In2S3 samples, TiO2/In2S3-12 composites with wedged structure show an obviously broadened absorption range and effectively enhanced visible light absorption, and thus excellent PEC performance. Under visible light condition, the photocurrent density of TiO2/In2S3-12 sample reaches to 0.1256 at 0 V vs. SCE (saturated calomel electrode), which is about 90 times higher than that of pure TiO2 film. The experimental results evidence not only the sensitization of wedged In2S3 but also good carrier separation efficiency of TiO2/In2S3 heterojunction, which renders an effective way to improve the PEC water splitting efficiency.