An electrospun transporter-assisted evaporator with antifouling water channels for solar-driven desalination and water purification

Interfacial solar steam generation is a promising, energy-efficient, and environmentally friendly technology in water purification. Most studies currently focus on the design of various light absorbers and improvement of energy conversion efficiency. However, there are few reports about how to enhance evaporation performance and water quality of evaporators in the treatment of oily water and seawater. Herein, this work demonstrates an electrospun transporter-assisted evaporator with antifouling water channels for water purification and desalination. The graphene oxide/polyacrylonitrile (GO/PAN) nanofibrous membrane as the photothermal layer can convert solar energy into heat for the vaporization of water. By in-situ crosslinking zwitterionic gel on a porous PAN nanofibrous strip as the water channel, the water channel can achieve a superwetting surface, thereby enhancing hydrophilicity and underwater superoleophobicity. The evaporator with the zwitterionic gel modified PAN (ZG-PAN) strip demonstrates the stable evaporation rate and prevented the adhesion of organic pollutants, meanwhile decreases the concentration of total organic carbon in the collected water. Additionally, anti-polyelectrolyte effect of the zwitterionic polymer reduces the salt deposition on the evaporation surface and maintains stable desalination performance. Our study provides an effective method to improve solar evaporation performance and product water quality during a long-term oily water or seawater treatment.