GO/PVA Array Structure Absorber for Efficient Solar Generation of Water Vapor

The graphene oxide (GO) was uniformly dispersed in a polyvinyl alcohol (PVA) aqueous solution, and dried to prepare a GO/PVA film with a smooth surface. The surface of GO/PVA film was treated by laser etching process to obtain LT-GO/PVA film, and the microstructure, physical properties of LT-GO/PVA film and its performance as a solar-thermal conversion device were investigated. The results show that the surface of LT-GO/PVA film forms a 3D porous array structure, which can promote the absorption of sunlight and reduce the energy loss caused by diffuse reflection. The surface of LT-GO/PVA film starts to change from hydrophilic to hydrophobic, which can enhance the evaporation and separation of water from LT-GO/PVA film surface. Under the light intensity of 1 kW/m², the evaporation rate of water is 1.827 kg/(m²·h), and the light-to-heat conversion efficiency is 89.4%.