Superhydrophilic CuS/PDA@PI nanofibrous aerogel with efficient synergistic solar-driven interfacial evaporation for water purification

Solar-driven interfacial evaporators represent a promising approach to alleviate global freshwater scarcity. However, practical applications still face challenges such as low evaporation efficiency, salt scale accumulation, and unstable evaporation. Therefore, we polymerized and deposited polydopamine (PDA) and hydrothermally synthesized CuS nanoparticles onto a polyimide (PI) aerogel to prepare a superhydrophilic porous CuS/PDA@PI nanofibrous aerogel. The aerogel achieved >97% light absorption over 200-2500 nm and a water evaporation rate of 1.963 kg m −2  h −1 under one sun irradiation (1 kW m −2 ). The apparent total evaporation efficiency reached 119.8%, exceeding the theoretical limit due to additional environmental heat harvesting. Even after 1200 min of cycling, the aerogel maintained an apparent total evaporation efficiency of 116.6%. The evaporator maintained an apparent total evaporation efficiency of 88.7% under a salt (20%) environment and exhibited self-cleaning performance. Furthermore, the aerogel exhibited purification performance for dye wastewater, acidic and alkaline solutions, and seawater. This superhydrophilic evaporator provides a viable route for practical seawater desalination.