Advanced layered nanocomposites with controllable aligned channels for efficient solar-driven desalination

Growing concerns regarding clean water scarcity have spurred significant interest in desalination technologies. While reverse osmosis membranes can efficiently remove salt and impurities, they typically consume high amounts of electrical energy due to their reliance on applied pressure. Moreover, conventional flat membranes often face issues such as fouling that leads to performance deterioration in the desalination process. Here, we report a 3D-structured advanced layered nanocomposites (ALN) aerogel for continuous desalination powered by solar energy (i.e., without requiring electrical energy, as is required by pressure-driven membrane desalination). This ALN incorporates hydrothermally synthesized LDH@MXene, and in combination with the TEMPO-mediated oxidation of delignified biomass (TODB), the ALN showcases exceptional photothermal performance (reaching temperatures of 85 °C) under sunlight irradiation (1 kWm^-2). This performance, which is superior to that achieved by other MXene-based SE, can be attributed to its high surface area and UV–Vis-NIR absorption capacity, and it ultimately results in a high water evaporation rate. Further, the internal aligned channels, which are fabricated through freeze-casting, play a crucial role in preventing salt crystallization, and they therefore enhance the continuous desalination performance of the system. Our findings ultimately suggest that ALN aerogels with controllable aligned channels represents a promising energy-efficient and sustainable alternative for clean water production.