Superhydrophobic aerogels with various pollutant removal properties and their application in solar water evaporation

Traditional superhydrophobic materials can selectively remove insoluble pollutants due to their non-wetting and superoleophilic property. However, the dissolved pollutants cannot be removed. In this paper, the surface of melamine sponge was hydrophobized through solvothermal method, through which insoluble pollutants could be selectively removed and dissolved pollutants could be adsorbed. Importantly, superhydrophobic melamine was used as the substrate combined with a hydrophilic layer (cotton) and a photothermal layer (GO/CNTs), which were designed to achieve an efficient water vapor production. The superhydrophobic sponge has excellent pH stability as well as mechanical stability. The adsorption efficiency was still maintained at 96.5% after three cycles of adsorption. It is found that the efficiency of water vapor production was increased by 5.4 times via the synergistic effect of the superhydrophobic, hydrophilic and photothermal layer. It is expected that new solutions for sewage purification could be provided through multifunctional material design methods.