Graphene-Based Double-Sided Light Absorption Evaporators with Enhanced Water Supply for Solar Desalination

The scarcity of fresh water resources poses a significant challenge to humanity; therefore, it is necessary to advance the development of a sustainable and highly efficient evaporator. However, the light absorption capability of traditional evaporators is limited to only the top layer, and the single-sided absorption characteristics impose constraints on their efficiency. Herein, we propose a novel method for manufacturing double-sided light absorption evaporators, which mainly includes porous carbon/ceramic nanofilm and graphene upper and lower films as the light absorption layer of the photothermal conversion evaporator, and then the hydrophilic film interlayer transfers water upward. The transmission rate of seawater is affected by the tilt angle at which the evaporator is inserted; therefore, identifying the optimal working angle becomes crucial. Under conditions of inclination angle (15–75°), the evaporation rate of the evaporator with the optimum tilt angle reaches 3.15 kg m–2 h–1. The results of outdoor experiments demonstrate that the double-sided evaporator exhibits an evaporation rate 0.7 kg m–2 h–1 higher than that of the single-sided during noon hours. Furthermore, we simulate the evaporation efficiency of outdoor sunlight at different tilt angles through COMSOL. The design of the double-sided evaporator offers a novel pathway for the future development of high-performance solar-driven evaporators in large-scale applications.