Self-rotating wood-based floating solar-driven interfacial evaporator for continuous and high-efficiency desalination

Self-cleaning solar-driven interfacial evaporation can mitigate reduced photothermal efficiency and evaporation rates due to salt accumulation, but traditional plastic spherical-based evaporators risk releasing microplastics during evaporation, posing environmental hazards. To overcome these challenges, this study developed a floating wood-based self-rotating evaporator system based on delignified wood spheres coated with polypyrrole (PPy/DWS), which utilizes naturally eco-friendly wood as the substrate, eliminating the risk of marine pollution, while its self-rotating mechanism effectively manages salt accumulation, ensuring sustained high-efficiency evaporation even in high-salinity environments. Experimental results demonstrated that the PPy/DWS evaporator achieved an optimal evaporation rate of 2.43 kg m −2 h −1 in 3.5 wt% saline solution under one sun irradiation, and maintained a rate of 1.52 kg m −2 h −1 even in a 20 wt% high-salinity solution, validating its efficiency and stability (> 8h) under various environmental conditions. This research provides critical technological support for clean water production and highlights the significant potential of the wood-based self-rotating system as a sustainable desalination and water purification solution.