High solar desalination efficiency achieved with three-dimensional Cu2ZnSnS4 nanosheetassembled membranes

Plasmonic structures are gaining tremendous interest due to their unique capability to trap light into subwavelength units, beneficial for high efficient light harvesting and related applications. Here, a plasmonic structure realized on a monocrystallized Cu2ZnSnS4 (CZTS) nanosheet-assembled membrane is presented. This unique CZTS structure exhibits high absorption efficiency (≈92.25%) in a broad solar spectrum (200–2500 nm), leading to a solar desalination efficiency of ≈84.5% under 1 Sun irradiation. This highly efficient broadband absorption is due to the structure induced localized surface plasmon resonance absorption. Besides, owing to its high chemical stability, salty water containing heavy metal ions can be effectively desalinated with a constant long time (>20 h) durability using this CZTS membranes as the absorber. The combination of the robust desalination effect, high stability and durability, as well as the low-cost and scalable process for production, makes this type of CZTS membranes one of the most competitive desalination candidates.