Hydrogel-based composite interfacial evaporators: Rapid preparation, contaminant control, and desalination

The solar interface evaporation system (SIES) is considered the most promising solution to water scarcity for humans because it can produce clean water from seawater and wastewater without consuming additional energy. In particular, the photothermal materials with high efficiency in photothermal conversion are essential for this system. In addition, it remains a challenge to achieve the rapid preparation of multifunctional self-floating SIES that can remove contaminants from water under mild conditions. In this paper, a high vapor flux of 2.37 kg•m −2 •h −1 was achieved by dehydration condensation of small-molecule sucrose to prepare coke and introducing it into a hydrogel-based composite evaporator. To meet the large-scale preparation, the whole process was shortened to less than 2 h with a mild environment. The self-floatability in SIES was provided by hydrophobic CNTs@Bi 2 WO 6 (SH-CNTs@Bi 2 WO 6 ) nanoparticles loaded onto different substrates while addressing the degradation of water pollutants. This paper provides a reference for environmental protection and wastewater treatment.