Hydrogels in solar-driven water and energy production: Recent advances and future perspectives

Hydrogels are emerging as an ideal platform for sustainable water and energy nexuses due to their low-cost, ease of processing, versatile functions, unique structural networks, and high adaptability. The establishment of a solar-thermal-electricity system assumes critical importance in achieving effective solar energy utilization. This review focuses on recent advances in hydrogel-enabled solar steam generation (SGG) and atmospheric water harvesting (AWH) systems and discuss their extended applications for renewable energy, such as thermal-electricity and green hydrogen generation. Furthermore, advanced material development and various engineering strategies are proposed to enhance water and energy generation efficiency, taking into account the fundamental structure–property-application relationships (SPAR). Finally, research challenges and future opportunities for fundamental studies and industrial implementation of hydrogel-based freshwater and renewable energy generation systems are put forward.