Iron diselenide/carbon black loaded mushroom-shaped evaporator for efficiently continuous solar-driven desalination.

ABSTRACT

Solar-driven desalination is an environmentally sustainable method to alleviate the problems of freshwater scarcity and the energy crisis. However, how to improve the synergy between the photothermal material and the evaporator to achieve high photothermal conversion efficiency simultaneously, excellent thermal management system and good salt resistance remains a challenge. Here, a mushroom-shaped solar evaporation device is designed and fabricated with iron diselenide/carbon black (FeSe2/CB) coated cellulose acetate (CA) film as mushroom surface and cotton swab as mushroom handle, which presented high solar-driven evaporation and excellent salt resistance. Thanks to the unique photothermal effect and the synergistic effect, the FeSe2/CB composites enabled a promising photothermal conversion efficiency of up to 65.8 °C after 180 s. The mushroom-shaped evaporation device effectively overcomes water transport and steam spillage channel blockage caused by salt crystallization through its unique vertical transport water channels and conical air-water interface. When exposed to real sunlight, the solar evaporation rate of the steam generation structure reached as high as 2.03 kg m-2 h-1, which is more than 13 times higher than natural evaporation. This study offered new insights into the higher solar-driven evaporation rate and salt-blocking resistance of the FeSe2/CB mushroom-shaped solar evaporation device for solar-powered water production.