Ran Niu, Jiaxin Ren, J. Justin Koh, Ling Chen, Jiang Gong*, Jinping Qu, Xiaodong Xu, Jalal Azadmanjiri, Jiakang Min*
Bio-inspired sandwich-structured all-day-round solar evaporator for synergistic clean water and electricity generation
Advanced Energy Materials (2023) Accept.
The integration of solar-driven interfacial evaporation and electricity co-generation is considered a promising approach to simultaneously alleviate freshwater scarcity and 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 which survive in extreme climates, we design all-weather solar-driven interfacial evaporators with a sandwich structure. 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 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 the 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 under 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.