Seawater Desalination by Interfacial Solar Vapor Generation Method Using Plasmonic Heating Nanocomposites

• Main Authors: Zhourui Xu, Nanxi Rao, Chak-Yin Tang, Wing-Cheung Law
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Series: Micromachines
• Subjects: plasmonic heating; nanorod; solar vapor generation
• Online Access: https://www.mdpi.com/2072-666X/11/9/867

With the ever-growing demand in fresh water supply, great efforts have been devoted to developing sustainable systems which could generate fresh water continuously. Solar vapor generation is one of the promising strategies which comprise an unlimited energy source and efficient solar-to-heat generators for overcoming fresh water scarcity. However, current solar vapor generation systems suffer either from inefficient utilization of solar energy or an expensive fabrication process. In this paper, we introduced a nano-plasmonic approach, i.e., a floatable nanocompoiste where copper sulfide nanorods (Cu_2-xS NRs) are embedded in a polyvinyl alcohol (PVA) matrix, for solar-to-vapor generation. A high solar vapor generation efficiency of ~87% and water evaporation rate of 1.270 kg m⁻² h⁻¹ were achieved under simulated solar irradiation of 1 sun. With the illumination of natural daylight, seawater was purified using Cu_2-xS NRs-PVA gel, with high purity, as distilled drinking water. The plasmonic nanocomposites demonstrated here are easy to fabricate and highly efficient for solar vapor generation, illustrating a potential solution for future seawater desalination.