Photocatalysis for synergistic water remediation and H2 production: A review

Photocatalysis offers an energy-efficient and environment-friendly route to alleviate energy crisis and environmental pollution. Sunlight-driven photocatalytic H2 production with synergistic degradation of pollutants can not only realize the conversion of solar energy to hydrogen energy, but also contribute to water remediation and preparation of organic by-products. In this paper, we adopt a binary analysis perspective to introduce the effects of photocatalyst types, composites, microstructure, pollutants properties, co-existing substances and different synergistic target on dual-functional photocatalytic activity. In addition, the influence mechanisms behind each factor, current challenges and future development directions are also comprehensively discussed. We found that the synergistic water remediation and H2 production system requires a balance between the two individual reactions, which requires not only a bi-directional adaptation of catalyst and pollutant, but also a comprehensive consideration of the reaction environment, i.e., achieving the trinity of pollutants/photocatalysts/co-existing media. Specifically, developing more efficient components and more suitable loading methods, constructing more optimized and innovative catalyst structures and clarifying the degradation mechanism of pollutants are crucial for efficient photocatalytic synergistic systems. This work provided a theoretical basis for the development of bifunctional photocatalytic systems.