Dual‐Zone Photothermal Evaporator for Antisalt Accumulation and Highly Efficient Solar Steam Generation

Abstract Interfacial solar steam generation offers a promising and cost‐effective way for saline water desalination. However, salt accumulation and deposition on photothermal materials during saline and brine evaporation is detrimental to the stability and sustainability of solar evaporation. Although several antisalt strategies are developed, it is difficult to simultaneously achieve high evaporation rates ( > 2.0 kg m −2 h −1 ) and energy efficiencies. In this study, a self‐rotating photothermal evaporator with dual evaporation zones (i.e., high‐temperature and low‐temperature evaporation zones) is developed. This photothermal evaporator is sensitive to weight imbalance ( < 15 mg) thus is able to quickly respond to salt accumulation by rotation to refresh the evaporation surface, while the dual evaporation zones optimize the energy nexus during solar evaporation, simultaneously realizing excellent salt‐resistant performance and high evaporation rate (2.6 kg m −2 h −1 ), which can significantly contribute to the real‐world application of solar steam generation technology.