BC/GO-Ag composite aerogel with synergistic enhanced photothermal performance for efficient solar water evaporation

Abstract

Solar water evaporation has great potential to alleviate the global freshwater crisis. Among them, photothermal materials have been widely studied as the core part of the solar water evaporation. However, its development is limited due to the complex preparation method and low evaporation efficiency. Herein, the composite aerogels based on graphene oxide (GO) and silver nanoparticles (Ag NPs) were developed by low-temperature-crosslinking method and in-situ reduction method and applied to solar interfacial evaporation. Due to the synergistic effect between the broadband light absorption of GO and the localized surface plasmon resonance effect of Ag NPs, the BC/GO-Ag composite aerogel has an optical absorption rate of 84.1%, an evaporation rate of 2.36 kg m-2h−1, and an evaporation efficiency of 94.5%, which is better than most of the previously reported photothermal materials. In addition, the material could be applied to various complex water environments. The BC/GO-Ag composite aerogel also showed good reusability. BC/GO-Ag composite aerogel is a promising material due to its simple and mild preparation method, environmental protection of raw materials, and high evaporation efficiency.