Biopolymer Hydrogel-Based Salt-Resistant Evaporator for Solar-Energy-Driven Desalination and Water Purification

Interfacial solar steam generation (ISSG) has recently received much attention as a low-carbon-footprint and high-energy-efficient strategy for seawater desalination and wastewater treatment. However, achieving the goals of a high evaporation rate, ecofriendliness, and high tolerance to salt ions in brine remains a bottleneck. Herein, a novel hydrogel-based evaporator for effective solar desalination was synthesized on the basis of sodium alginate (SA) and carboxymethyl chitosan (CMCS) incorporating a carbon nanotube (CNT)-wrapped melamine sponge (MS) through a simple dipping-drying-cross-linking process. The hydrogel-based evaporator reaches a high evaporation rate of 2.18 kg m