Strategies for enhancing the photothermal conversion efficiency of solar-driven interfacial evaporation

Solar-driven interfacial evaporation (SIE) represents a sustainable and efficient technology for the production of clean water, offering significant potential for applications in wastewater treatment and seawater desalination. To date, numerous ingenious designs have been developed to improve the efficiency of photothermal conversion in SIE systems. Based on enhancing sunlight absorption and reducing heat loss, the molecular design of organic photothermal materials in SIE systems and the structural design strategy of the evaporator (reducing sunlight loss, thermal management, water supply control) are comprehensively summarized and discussed. Organic photothermal materials with advantages such as molecular tunability and favorable biocompatibility are introduced to illustrate that in addition to common photothermal materials, organic photothermal materials also have excellent application potential for SIE technology. This review also summarizes the relevant efforts in repurposing exhausted heavy metal adsorbents and polyesters into evaporators, driven by considerations of economic costs and environmental sustainability. Finally, challenges and prospects facing the current advancement of SIE technology are discussed, with a focus on addressing potential issues in both fundamental research and practical applications. We envision that this review will offer valuable insights for the design of efficient, environmentally sustainable, and cost-effective SIE systems, thereby contributing to the accelerated development of high-performance technologies.