Micro–Nano Water Film Enabled High-Performance Interfacial Solar Evaporation

Interfacial solar evaporation holds great promise to address the freshwater shortage.However,most interfacial solar evaporators are always fllled with water throughout the evaporation process,thus bringing unavoidable heat loss.Herein,we propose a novel interfacial evaporation structure based on the micro–nano water fllm,which demonstrates signiflcantly improved evaporation performance,as experimentally verifled by polypyrrole-and polydopamine-coated polydimethylsiloxane sponge.The 2D evaporator based on the as-prepared sponge realizes an enhanced evaporation rate of 2.18 kg m-2 h-1under 1 sun by flne-tuning the interfacial micro–nano water fllm.Then,a homemade device with an enhanced condensation function is engineered for outdoor clean water production.Throughout a continuous test for 40 days,this device demonstrates a high water production rate（WPR） of 15.9–19.4 kg kW-1 h-1 m-2.Based on the outdoor out- comes,we further establish a multi-objective model to assess the global WPR.It is predicted that a 1 m2 device can produce at most 7.8 kg of clean water per day,which could meet the daily drinking water needs of 3 people.Finally,this technology could greatly alleviate the current water and energy crisis through further large-scale applications.