Achieving Solar‐Thermal‐Electro Integration Evaporator Nine‐Grid Array with Asymmetric Strategy for Simultaneous Harvesting Clean Water and Electricity

Abstract Water evaporation is a ubiquitous and spontaneous phase transition process. The utilization of solar‐driven interface water evaporation that simultaneously obtains clean water and power generation can effectively alleviate people's concerns about fresh water and energy shortages. However, it remains a great challenge to efficiently integrate the required functions into the same device to reduce the complexity of the system and alleviate its dependence on solar energy to achieve full‐time operation. In this work, a multifunctional device based on reduced graphene oxide (RGO)/Mn3O4/Al2O3 composite nanomaterials is realized by an asymmetric strategy for effective solar‐thermal‐electro integration that can induce power generation by water evaporation in the presence/absence of light. Under one sun irradiation, the solar‐driven evaporation rate and output voltage are 1.74 kg m−2 h−1 and 0.778 V, respectively. More strikingly, the nine‐grid evaporation/power generation array integrated with multiple devices in series has the advantages of small volume, large evaporation area, and high power generation, and can light up light‐emitting diodes (LEDs), providing the possibility for large‐scale production and application. Based on the high photothermal conversion efficiency and power production capacity of the RGO/Mn3O4/Al2O3 composite evaporation/generator, it will be a promising energy conversion device for future sustainable energy development and applications.