PbS dendrites/graphene membranes as efficient solar steam generators

: Solar steam generation is a low-cost and facile process to generate clean water. Novel solar absorbers with broad solar light absorption and excellent photothermal conversion rates should be developed to achieve higher evaporation performance. : The PbS dendrites (PCA) were synthesized by a microwave-assisted hydrothermal process using surfactant and ionic liquid. The PCA and PbS-graphene composites (PCA-G) were loaded on filter paper to prepare the solar evaporators. The surface compositions, morphology, and optical properties of PCA and PCA-G nanomaterials were studied. The effects of loaded PbS amounts and graphene on the photothermal conversion, surface hydrophilicity, water penetration, and solar steam generation of the PCA/F and PCA-G/F films were investigated. The stability, reusability, salt-antifouling, and desalination performance of the PCA-G/F films were evaluated. The PbS dendrites were applied to solar steam generation for the first time. Incorporating PbS dendrites and graphene on the filter paper enhances light absorption and photothermal conversion. Besides, introducing PbS with dendritic (pine tree-like) structures prevents the close contact of PbS dendrites after stacking, facilitating the formation of hydrophilic interconnected porous structures as water-transporting channels. The evaporation rates of water and salt water were effectively improved. Furthermore, the water evaporation rates remained stable after five cycles.