Two-dimensional defective tungsten oxide nanosheets as high performance photo-absorbers for efficient solar steam generation

Abstract Efficient solar-driven evaporation has engendered great interests as a sustainable and environmental approach for solar energy utilization. The development of high-performance photo-absorbers is of paramount importance for realizing efficient solar evaporation. Among the light-harvesting materials, transition metal oxide (TMO) is regarded as one of the most promising substitutes for photothermal conversion. Here, two-dimensional (2D) defective tungsten oxide (WOx) nanosheets are prepared via introducing oxygen vacancies in WO 3 . It demonstrates that the novel 2D plasmonic WOx nanosheets can be used as high performance photo-absorbers for efficient solar steam generation, displaying broadband and intense light absorption in the full solar spectrum due to the tunable localized surface plasmon resonances. Its evaporation efficiency reaches ~ 78.6% under 1 kW/m 2 (one sun) irradiation. The result reveals that adjusting the surface nanostructures and morphologies of TMO can be thought to be a potential strategy to promote the light-harvesting performance for solar steam generation. This study is significant for further exploring potential applications of plasmonic semiconductors in sterilization, desalination, and photothermal power through solar steam generation.