PVA/CNT/PPy Aerogels for Driving Water Evaporation Through both Photo-Thermal and Electro-Thermal Effects

Solar-driven interfacial water evaporation technology is considered as a promising clean water production strategy addressing the issues of global water pollution and scarcity. In this study, highly efficient polyvinyl alcohol/carbon nanotube/polypyrrole (PVA/CNT/PPy) aerogel evaporator is fabricated by combining hydrophilic PVA aerogel with superior water absorption property and carbon-based fillers with coupled photo-thermal conversion effects. By regulating the pore structure of PVA aerogel, the capillary effect is enhanced, thereby optimizing the water transport rate. Based on the photo-thermal effect, the evaporation rate of the evaporator under one standard solar irradiation (1 kW m −2 ) is 3.17 kg m −2 h −1 . Additionally, after the input of electrical energy, the heat converted from light absorbed by carbon-based material can promote the Joule heating effect, and the synergistic effect further increases the evaporation rate of the aerogel to 5.59 kg m −2 h −1 when subjected to one solar irradiation combined with a 5 V input voltage. This electro-thermal assistance enables efficient water evaporation even in low-light and dark conditions. Furthermore, the PVA/CNT/PPy aerogel evaporator demonstrates significant potential in terms of desalination performance and long-term stability.