Bio-Inspired Sandwich-Structured All-Day-Round Solar Evaporator for Synergistic Clean Water and Electricity Generation

The integration of solar-driven interfacial evaporation and electricity co-generation is considered a promising approach to simultaneously alleviate freshwater scarcity and the energy crisis. However, affected by intermittent solar irradiation/uncontrollable weather, the overall performance of solar-driven evaporation in the real world is greatly reduced. Herein, inspired by antifreeze proteins in beetles that survive in extreme climates, all-weather solar-driven interfacial evaporators with a sandwich structure are designed. The top and bottom layers composed of MnO2-modified cotton cloth are used for photothermal conversion and water transport, meanwhile, the middle layer made of a phase change microcapsule/hydrogel composite serves for heat storage and release. Under 1 kW m(-2) irradiation, the evaporator exhibits a high evaporation rate of 2.67 kg m(-2) h(-1) and an efficiency of 89.5%. In the dark, the heat released from the phase change layer supports an evaporation rate of 0.43 kg m(-2) h(-1), 3.6 times that of pure water. Additionally, assembled with a thermoelectric module, the hybrid device achieves a stable output electricity power of 0.42 W m(-2) under 1-sun illumination and a prolonged output for 30 min in the dark. This work provides a novel approach for full-time solar-powered steam-electricity co-generation and a proof of concept for biomimetic steam generation/heat management integration.