A split salt-resisting evaporator system for highly efficient solar desalination

Solar-driven interface evaporation technology is expected to decrease heat loss and enhance solar thermal energy conversion efficiency. Despite its advantages, this technology still faces challenges, such as solar intermittence and interfacial salt accumulation during long-term operation. To address these issues, our study proposes a split solar desalination system comprising a heat collector module and a distillation module. The collector module consists of a metallic dovetail cavity and a phase-change energy storage material. The vulcanized dovetail cavity structure achieves broad-spectrum absorption and improves the photothermal conversion efficiency. The delay enthalpy of the phase change energy storage material effectively compensates for the intermittent heat loss caused by irradiation. The temperature-controlled motor brush water supply structure in the distillation module, combined with a gridded evaporation interface, prevents salt accumulation and achieves self-cleaning at the interface. Desalination of seawater in cloudy weather achieved freshwater productivity of 0.762 kgm−2 per hour, and there was no obvious salt accumulation at the evaporation interface. This work provides ideas for the practical application of solar-driven evaporation in the field of seawater desalination.