Salt-tolerant and low-cost flame-treated aerogel for continuously efficient solar steam generation

Interface solar-driven evaporation is a very promising technology used in solar energy harvesting, seawater desalination and water purification. However, salt accumulation is still a serious problem that hinders the long-term stable operation of the evaporator. Herein, we use natural wood with inherent porosity to develop a flexible cellulose aerogel, which can be used as efficient and stable solar evaporator for desalination after simple surface carbonization. This aerogel evaporator achieves a solar steam efficiency of 83.4% and an evaporation rate of 1.40 kg m−2 h−1 under the sunlight intensity of 1 kW m−2. In the simulated evaporation experiment for 7 days, the evaporator shows a stable evaporation rate (about 1.39 kg m−2 h−1), indicating the potential for long-term operation. In addition, the evaporator has the ability to resist salt accumulation and self-cleaning. The low cost, simple preparation and multiple functions make the evaporator promising to be a continuous and stable installation for solar desalination.