MXene sediment/AgNW-filled PVA-PAAm aerogels for efficient solar-driven seawater desalination

Waste-derived MS was upcycled as the main photothermal filler. • Aligned channels and GLYMO network enabled water transport and stability. • STA/Raman analyses supported confined-water enthalpy reduction. • AgNWs coupled with MS enhanced evaporation performance. Solar-driven interfacial evaporation offers an efficient route for alleviating freshwater scarcity, but its practical performance strongly depends on the rational integration of photothermal fillers, water-transport pathways, and thermally insulating matrices. Herein, MXene sediment (MS), a byproduct generated during MXene preparation, was reutilized as a waste-derived photothermal filler and incorporated with a low loading of silver nanowires (AgNWs) into a GLYMO-crosslinked poly (vinyl alcohol)/polyacrylamide (PVA/PAAm) aerogel. The vertically aligned microchannels and superhydrophilic polymer network provided continuous water transport, while the GLYMO-reinforced organic–inorganic network improved structural robustness. In addition, the broadband absorption of MS and AgNW-assisted optical enhancement enabled a solar absorptance of approximately 95%. Under 1 sun illumination, the optimized PPAMS 20 @AgNWs evaporator achieved an evaporation rate of 3.21 kg m −2 h −1 and an effective-enthalpy-based solar-to-vapor efficiency of approximately 97%. It also exhibited stable repeated-operation performance over 25 cycles and good salt-resistant behavior under the tested high-salinity conditions. This work demonstrates a potential strategy for converting MS into a functional photothermal filler for solar-driven seawater desalination. Working Principle, Testing, and Exploration of the PPAMS Interface Evaporator. Download: Download high-res image (310KB) Download: Download full-size image