Heterostructure design of Cu2O/Cu2S core/shell nanowires for solar-driven photothermal water vaporization towards desalination

Abstract

Solar-driven water evaporation has been considered as a promising strategy to solve the growing water shortage and water pollution problems. Developing low-cost and large-scale photo-thermal materials combined with highly efficient solar steam generation, water transport and environmental stability still remains a huge challenge. Herein, we proposed a design of Cu₂S/Cu₂O/Cu foam (Cu₂S/Cu₂O/CF) hierarchical structure through the interface engineering approach. The heterostructure contains the unique Cu₂O/Cu₂S core–shell nanowire and Cu foam substrate. The as-prepared Cu₂S/Cu₂O/Cu nanostructure achieved a high light absorption performance (96%), a high evaporation rate of 1.44 kg m⁻² h⁻¹ and a solar thermal conversion efficiency of 83.1% under 1 sun irradiation. The antifouling ability makes Cu₂S/Cu₂O/CF flexible in various kinds of water including polluted water and seawater. In addition, its excellent hydrophilic properties provide Cu₂S/Cu₂O/CF with anti-oil pollution capability, improving efficient water transport to the evaporator surface and purifying the raw water. The Cu₂S/Cu₂O/CF nanocomposite provides a promising route for freshwater production via solar distillation.