ABSTRACT:Interfacial solar desalination offers a promising approach to tackle global freshwater scarcity. However, achieving stable evaporation while simultaneously producing freshwater and collecting salt remains challenging. Here, we developed a hierarchical gradient-structured nanonets membrane (PF/EVOH/CNTs) by simple spray- coating poly(ethylene-co-vinyl alcohol) (EVOH) nanofibers and single-walled carbon nanotubes (SWCNTs) onto a commercial filter paper (FP) substrate. When the amount of SWCNTs is 0.3 wt%, the membrane's gradient nanonets architecture and superhydrophilicity enable efficient separation of oil-in-water emulsions. Leveraging its flexibility, we constructed a 3D mangrove-inspired evaporator, which achieves an evaporation rate of 2.43 kg m^-2h^-1 and an exceptional energy conversion efficiency of 128% under 1-sun illumination. The 3D design facilitates edge-preferential salt crystallization, allowing automatic detachment under gravity, yielding 3.44 g of salt at a rate of 43.14 g m^-2 h^-1 —twice that of a 2D counterpart. This work presents a multifunctional platform integrating oil-water separation, desalination, and salt recovery, advancing solar-driven water purification technologies.