Facile and Scalable Fabrication of Surface‐Modified Sponge for Efficient Solar Steam Generation

Abstract Solar steam generation is a highly promising technology for harvesting solar energy and desalination. Here, a new solar steam generation system is introduced based on a surface‐modified polyurethane sponge with bilayered structures for efficient solar steam generation. The top layer, coated with polydimethylsiloxane‐modified graphite powder, serves as light‐to‐heat conversion layer with a broad optical absorption, whereas the lower part of the sponge acts as a thermal insulator with a low thermal conductivity in the wet state (0.13882 W m −1 K −1 ). In addition, the strong hydrophobic wettability of the top layer (water contact angle: 148°) enables self‐floating behavior on water, which is beneficial for practical applications. The results show that compared with a silver‐nanoparticle‐doped sponge and an…