An efficient and scalable strategy for ultrablack-paint-enabled solar-driven steam generation

Solar-driven interfacial steam generation for desalination has attracted broad attention. However, a significant challenge still remains for achieving a high evaporation rate and high water quality, together with an easy-to-manufacture device to provide a feasible solar-driven steam generation system. In this study, a novel ultrablack paint, Black 3.0, serving as a satisfactory photothermal material is sprayed into the hot-pressed melamine foam networks, allowing us to construct an ultrablack and self-floating evaporation device. The high performing features of effective solar absorption and salt-rejection capability contribute to a high evaporation rate of freshwater at 2.48 kg m−2 h−1 under one sun (1 kW m−2). This interfacial solar evaporator has a daily drinkable water yield of 2.8 kg m−2 even in cloudy winter weather and maintains stability in water with a wide range of acidity and alkalinity (pH 1 ∼ 14). All commercially available raw materials and scalable fabrication approaches offer us a feasible and affordable manner to enable the construction of a highly-efficient solar steam generation system for freshwater production.