Robust and versatile polypyrrole supramolecular network packed photothermal aerogel for solar-powered desalination

Abstract

Solar-powered desalination is an emerging and sustainable water purification technology, that extends accessible clean water to relieve global water scarcity. Although great achievements have been made to develop interfacial photothermal materials, it is still challenging to simultaneously achieve high-level evaporation rates (>3 kg·m−2·h−1, 1 sun) and high-efficient energy conversion (>95 %) under 1 sun illumination. Herein, a polypyrrole supramolecular network-packed photothermal aerogel is designed and developed as solar-thermal evaporator to boost highly efficient solar-powered desalination. The photothermal aerogel integrates the photothermal, hydrophilic, and nanostructured polypyrrole supramolecular network to intensify solar-thermal energy utilization and reduce evaporation enthalpy, and the heat-insulating polysiloxane aerogel to enable mass transfer and suppress heat loss. The combined merits of the polypyrrole supramolecular network-packed photothermal aerogel promise outstanding evaporation rate of 3.61 kg·m−2·h−1 and remarkable solar-to-vapor conversion efficiency of 97.1 % under 1 sun illumination. Furthermore, polypyrrole supramolecular network imparts reliable salt resistance, cyclic stability, and environment tolerability for potential applications in solar seawater desalination. The comprehensive performance has considerable advantages over state-of-the-art materials. The study provides a new paradigm for the design of solar-thermal composites to advanced solar-powered desalination and contributes to future sustainable environmental and energy applications.