Radiative Layered Nanofiber Aerogel with Superior Salt-Resistant and Antibacterial Properties for Efficient Solar-Driven Interfacial Evaporation

Solar interfacial evaporation has gained considerable attention as a sustainable and eco-friendly desalination technology. However, challenges including limited water transport, salt crystallization, biofouling, and insufficient long-term stability remain critical. In this work, a radiate-layered graphene nanoplatelets/poly(vinyl alcohol-co-ethylene) (GN/EVOH) nanofiber aerogel was fabricated through graphene nanosheet-induced assembly and radial ice-templating. This hierarchical structure promotes synergistic vertical and radial transport of water and salt ions, effectively suppressing salt accumulation. The incorporation of graphene also imparts strong antibacterial properties to the evaporator. Under 1 sun illumination (1 kW m^-2), the aerogel achieved a high evaporation rate of 2.14 kg m^-2 h^-1 with an energy conversion efficiency of 98%. It maintained stable performance over multiple cycles in 20 wt % brine without salt crystallization, demonstrating excellent salt resistance. Moreover, the evaporator exhibited effective purification of simulated seawater, dye wastewater, acidic/alkaline solutions, and oil-water emulsions. These results indicate that the designed evaporator holds strong potential for practical applications in seawater desalination and wastewater treatment.