Interfacially synergistic Photothermal enhancement for solar evaporation by palygorskite-carbon nanotube/chitosan aerogels

With the escalating global water crisis, solar-driven interfacial evaporation has garnered significant attention as a sustainable desalination technology. However, it still faces challenges such as low evaporation efficiency, salt accumulation, and insufficient durability under real-world conditions. To address these issues, this study used chitosan (CTS) as a matrix to disperse carbon nanotubes (CNTs) with the assistance of palygorskite (Pal). The resulting Pal-CNTs composites were incorporated into the CTS matrix to prepare high-performance aerogels aimed at enhancing solar interfacial evaporation efficiency. The results show that Pal effectively prevents CNT aggregation, enabling uniform dispersion within the CTS matrix and resulting in enhanced light absorption and thermal management. Inspired by the multichannel structure of plant xylem, CTS/Pal/CNTs composite aerogels (CPC) with vertical pores were fabricated using directional freeze-drying. The combination of superhydrophilicity imparted by CTS and Pal, along with the vertical pore structure, allows the CPC to efficiently store and transport water. The CPC can produce up to 13.1 kg m −2 of water per day in outdoor conditions. Moreover, the vertical pore architecture and continuous water supply enable rapid salt diffusion, effectively resisting salt crystallization and maintaining stable performance even in high-salinity brine. The resulting solar evaporator also demonstrates robust mechanical strength and long-term stability, showing great potential for practical freshwater production.