Chinese yam-derived aerogel as a versatile platform for efficient freshwater production and pollution remediation

Abstract

Water scarcity and pollution have become major obstacles to sustainable global development. The development of a versatile platform that can simultaneously produce clean water and remediate pollutants from water is highly desirable but still difficult to realize. Herein, to address this challenge, we have developed a CY@PPy@Ag aerogel with excellent photothermal and photocatalytic capabilities through a freeze-drying process, followed by polypyrrole coating and Ag deposition. The excellent characteristics, including broad-spectrum light absorption (97.2%), localization of converted heat, rapid water transport, and porous open microchannels, enabled it to act as an advanced solar evaporator for efficient and continuous steam generation without salt crystallization. Moreover, the high evaporation rate (1.51 kg m−2 h−1) was maintained even in high concentrations of brine and real seawater. Taking advantage of its enhanced photocatalytic performance, organic dyes in water could be rapidly and completely decomposed by the CY@PPy@Ag aerogel under solar irradiation, and this photodegradation process was significantly accelerated with the help of NaBH4. This work is expected to provide a one-stone-two-birds strategy to simultaneously achieve clean water harvesting and pollution remediation, which holds great promise in the fields of solar energy harvesting, wastewater treatment, and seawater desalination.