Preparation of Photothermal Conversion Cotton Fabric Via in Situ Grafting Polyaniline for Highly Efficient Solar-Driven Interfacial Brine Evaporation

As an emerging efficient and sustainable technology, solar-driven interfacial evaporation (SDIE) has great potential to tackle the freshwater crisis by purifying water from brine or wastewater, in which photothermal conversion materials (PCMs), play a primary and critical role. Herein, we report a novel method for batch fabrication of photothermal conversion cotton fabric (PCCF) by co-irradiation grafting polymerization of 4-aminostyrene and in situ grafting polymerization of aniline in sequence. The obtained photothermal cotton fabric not merely exhibited a high evaporation rate of 1.47 kg m-2 h-1 when treating 3.5 wt.% NaCl solution with evaporation efficiency of 97% performed on a simple tilted platform (under 1 kW m-2 of power density), but also showed excellent stability for outdoor natural evaporation over 60 days. And the tilted solar evaporator also exhibited a high evaporation rate (1.38 kg m-2 h-1) in the saturated NaCl solution (26 wt.%), suggesting a great potential to the application to evaporative crystallization of inorganic salts. The promising strategy adopted here could be employed to facilitate the scale-up preparation of PCMs and address current challenges in high-efficiency and sustainable solar-driven seawater desalination, even zero liquid disposal of industrial waste brine