Enhancement of Interfacial Solar Vapor Generation by Environmental Energy

For the first time, we demonstrated that careful structural designs can exploit environmental energy to enhance the performance of an interfacial solar vapor generation device to well above the theoretical limit of vapor output, assuming 100% solar-to-vapor energy transfer efficiency, under various light intensities. This concept can have direct implications in various important processes, such as wastewater treatment. Since interfacial solar vapor generation has garnered increasing interest, significant efforts have been made to tailor nanomaterials to achieve high solar-to-vapor transfer efficiency and high evaporation rate. It is generally considered that the evaporation rate is limited by solar irradiation, assuming 100% solar-to-vapor energy transfer efficiency. Here we report that the evaporation rate can be well above the assumed limit by exploiting energy input from the environment. This finding demonstrates a new route to enhance the evaporation rate to a higher level. For the environmental energy-enhanced interfacial solar vapor generator, through elegant structural designs, there will be a net energy gain from the environment during the solar vapor generation, yielding an evaporation rate exceeding the theoretical value, assuming a 100% solar-to-vapor energy transfer efficiency.