Robust light-driven interfacial water evaporator by electrospinning SiO2/MWCNTs-COOH/PAN photothermal fiber membrane

Desalination technology by interfacial water evaporator is meaningful to solve the increasing global freshwater shortage. Herein, we prepared an efficient and lightweight silicon dioxide/carboxylated multi-walled carbon nanotube/polyacrylonitrile (SiO2/MWCNTs-COOH/PAN) fiber membrane by electrospinning. And then an interfacial water evaporator was assembled by attaching it onto a piece of filter paper with insulation polystyrene (PS) foam used as support material, and cotton yarns (CYs) used for water transportation. The advantages of this design can prevent heat from dissipating to the bulk water and ensure good evaporation efficiency. The composite fiber membrane exhibited an excellent evaporation rate of 1.28 kg m(-2) h(-1) and a superior photothermal conversion efficiency of 82.52% under 1 sun illumination (1000 W m(-2)). Water absorption capability was also demonstrated by MMT, CA and capillary effect tests, while thermal management capacity was analyzed by infrared thermal imaging camera. Furthermore, the prepared composite fiber membrane remained stable evaporation rate and high efficiency even after standing 20 repeated evaporation cycles. Thus, this interfacial water evaporator prepared by this work has an outstanding photothermal conversion capability and will be a promising candidate used for solar-driven seawater desalination.