Photocatalytic decomposition of shale gas flowback water producing hydrogen by S-scheme heterojunction NiTiO₃/CdS

Constructing S-scheme heterojunction is an effective strategy to form photocatalytic materials with strong reduction property and improve photocatalytic performance. In this paper, NiTiO₃/CdS photocatalytic materials with S-scheme heterostructures were prepared by a simple hydrothermal method. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), specific surface area analysis and Ultraviolet-visible diffuse reflection spectroscopy (UV-vis DRS). The hydrogen production performance was tested by the photocatalytic hydrogen production experiment from shale gas flowback water. The results showed that NiTiO₃ and CdS were successfully compounded. In addition, 15% NiTiO₃/CdS showed the optimum hydrogen production performance (1568.9 µmol/(g·h)), and excellent recycling potential. This work is of great significance for the exploration of efficient and stable photocatalysts with S-scheme heterojunctions, the efficient utilization of wastewater and the alleviation of energy shortages.