Electroless Plating Preparation of Biomimetic Nickel-Black/Graphene Membranes for Solar-Driven Interfacial Evaporation

Solar-driven interfacial evaporation offers a promising approach to efficient photothermal conversion. Inspired by the efficient light-trapping effect property observed in the textured bark of the <i>Sophora japonica</i> tree, this study successfully developed a bark-like, hierarchical nickel-black/graphene photothermal conversion membrane (E-Ni/Gr) via electroless plating. The hierarchical architecture contributes to light entrapment, while the synergistic effect between the intrinsic semiconductor absorption bandgap and the broadband absorption of the carbon component jointly enhances optical absorption, achieving an absorption efficiency of 83.21%. Under 1 kW·m^-2 irradiation, the evaporation rate of E-Ni/Gr-20 (adding 20 mL of graphene suspension solution) reached 1.62 kg·m^-2·h^-1, with a photothermal conversion efficiency of 91.25%. The membrane also presented remarkable stability (maintaining an evaporation rate of 1.3 kg·m^-2·h^-1 after 20 cycles) and desalination performance (NaCl rejection >99%). This study offers valuable perspectives for the development of efficient and stable bioinspired photothermal materials.