Antibacterial chitosan aerogel with vertical pores and PPy@GO synergy for efficient solar desalination

The global freshwater shortage underscores the urgent need for efficient and sustainable desalination technologies. Solar-driven evaporation offers a promising solution due to its low energy demand and environmental compatibility, with photothermal materials and evaporator design being key to enhancing performance. In this study, chitosan-based aerogels have been used as the substrate, and a vertical channel structure has been prepared through unidirectional freezing technology in fabricating PPy@GO-CG (polypyrrole@graphene oxide-chitosan) aerogel evaporators. Experimental results have showed that under 1 kW·m −2 simulated solar light, the water evaporation rate can reach 3.79 kg·m −2 ·h −1 , and the solar steam conversion efficiency is as high as 96.16 %. In saline conditions, salt accumulation was not observed until after 60 h of continuous irradiation, indicating strong salt-rejection capability. The evaporator exhibits excellent long-term stability, salt resistance, and inherent antibacterial properties, ensuring both efficiency and reliability for practical use. This work thus offers a promising strategy for solar-driven seawater desalination and thermal energy conversion.