Thermal and electrical conductive 2D CuO evaporator for all-day steam generation

Solar energy-driven water evaporation is an effective way to obtain clean water through seawater desalination. Due to the day and night cycle, all-day steam generation is an urgent project. Here, 2D evaporators with effective heat management were designed and constructed by facile folding, in which superhydrophilic CuO coatings with honeycomb-like pores were in situ deposited on brass plates via electroplating and heat oxidation. In the daytime, the 2D evaporator has excellent photothermal performance due to the appropriate pore structure, light absorption, and water supply. The evaporation rate reaches 1.4 kg m- 2 h-1, and the energy conversion efficiency of 93.5% under 1 sun in 3.5% artificial seawater for ten cycles. Except for solar-driven water evaporation, some heat converts into electricity due to the temperature difference between the two surfaces of the high thermal conductive 2D evaporator. At night, steam is generated through the flexible photoelectric transition. The evaporation rate is 5.8 kg m- 2 h-1 at an input voltage of 6 V. The stable evaporation performance of this evaporation system and the advantages of all-day steam generation show considerable prospects. It may be widely used in pure water production in the future.