Recent Advances in Solar-Driven Photothermal Conversion Hydrogels: A Review

Solar energy is an inexhaustible clean energy. Owing to the shortage of fossil fuels and the development of science and technology, increasing attention is being paid to the use of solar energy. Photothermal conversion (PC) materials are crucial for effectively acquiring and converting solar energy. At present, various PC materials have shown considerable potential, particularly PC hydrogels, a new type of PC material that has been increasingly studied by researchers in recent years. In this study, the characteristics, preparation methods, and PC efficiencies and mechanisms of PC hydrogel materials are reviewed. The main features of photothermal materials such as precious metals, semiconductors, carbon-based materials, and polymer materials are also comprehensively analyzed. In addition, the applications and research progress of PC hydrogels in the fields of seawater evaporation, wastewater purification, organic compound degradation, photocatalytic hydrogen production, and carbon dioxide conversion are examined. Finally, the development prospects and challenges associated with PC hydrogels are evaluated. This study is expected to have a positive significance for the development of new PC hydrogels for the efficient utilization of solar energy.