Coral Skeletons as Efficient Interfacial Solar Evaporators

Solar evaporators based on biomaterials have received intensive attention because they are biocompatible, carbon-rich, and hydrophilic with low thermal conductivity and excellent solar absorption. Here, we report a photothermal interfacial evaporator based on the porous biomass coral skeleton (CS/Fe) for interfacial solar evaporation for the first time. It exhibited a water evaporation rate of approximately 2.44 kg m–2 h–1, five times more than that of pure water under one solar irradiation. It is demonstrated that the capability of high solar steam generation is attributed to the unique porous structure and interconnected channels of the coral skeleton, as well as the strong photothermal effect of Fe3O4 nanoparticles. These features not only provide efficient solar absorption and water transport but also suppress heat loss at the same time. Therefore, our solar evaporator is a low-cost and efficient means of interfacial solar evaporation, and it provides insights into the design of effective photothermal evaporators based on biomaterials.