A bioinspired hydrogel with tailored nano-topography and desired mechanical performance for highly efficient solar-driven water purification

Abstract

Solar-driven interfacial evaporation has emerged as a sustainable and innovative technology for efficient, clean water production. Despite the tremendous progress made to date, to achieve materials with excellent mechanical performances, efficient energy utilization, and high salt-resistance, high cost and delicate nanostructures pose challenges. Here, a composite hydrogel with rationally architected skeletons is constructed through facilely combining salting-out treatment and an in situ polymerization strategy. Benefiting from the unique pore structure, coral-like wrinkle surface micro-/nano-topologies, and well-interpenetrative channels, the constructed hydrogel exhibits an outstanding mechanical tensile strength of ∼1.41 MPa, an ultrahigh evaporation rate of 2.62 kg m⁻² h⁻¹ and a solar-to-vapor efficiency of 93.78% under 1 sun irradiation. This work demonstrates a new hydrogel evaporator structure and also provides a perspective for the structural design of next-generation good mechanical performance, durable, salt-tolerant and high-efficiency interfacial steam generators.