Multifunctional Solar Evaporator with Adjustable Island Structure Improves Performance and Salt Discharge Capacity of Desalination

Interfacial solar steam generation (ISSG) is the main method to get fresh water from seawater or wastewater. The balance between evaporation rate and salt resistance is still a major challenge for ISSG. Herein, a wood aerogel island solar evaporator (WAISE) with tunable surface structure and wettability by synthesizing poly(n‐isopropylacrylamide)‐modified multi‐walled carbon nanotube photothermal layers. Compared to dense surface structure evaporators, interfacial moisture transport, thermal localization, and surface water vapor diffusion of WAISE are greatly promoted, and the evaporation rate of WAISE increased by 87.64%. WAISE allows for record performance of 200 h continuous operation in 20% NaCl solution without salt accumulation. In addition, the photo‐thermal‐electric device is developed based on WAISE with continuous water purification, power generation, and irrigation functions. This work provides a new direction for the development of multifunctional water purification systems. In this paper, a wood aerogel island solar evaporator (WAISE) with tunable surface structure and wettability is prepared by synthesizing a poly(n‐isopropylacrylamide)‐modified multi‐walled carbon nanotubes photothermal material. WAISE has effectively balanced the contradiction between evaporation rate and salt tolerance, so that this work provides a new research idea for the application of a wood evaporator in seawater desalination.