A Novel Flake-like Cu₇S₄ Solar Absorber for High-Performance Large-Scale Water Evaporation

Solar-driven interfacial evaporation has received increasing attention due to its energy conversion efficiency being higher than that of conventional photothermal utilization. Although tremendous photothermal materials for solar-driven interfacial evaporation have been reported, the high cost and complex preparation process hinder their worldwide application. Herein, a Cu7S4 nanosheet on Cu mesh (Cu7S4/Cu mesh) as a novel photothermal material with superior water evaporation performance was rapidly synthesized by a facile wet chemical method. This material owns a high absorptivity of 95.7% within the wavelength range of 0.25–2.5 μm. Meanwhile, a good hydrophilicity makes water wet the material easily, which is favorable for solar-driven interfacial evaporation. The evaporation rate and efficiency of the material reach 1.41 kg m–2 h–1 and 88.1% under 1 kW m–2, respectively, which is three times as large as those without the absorber and also superior to some reported photothermal materials. Moreover, the low-cost, simple, and efficient preparation method is beneficial for large-scale production. This work provides a scalable and facile avenue for synthesizing a highly efficient Cu7S4/Cu mesh solar water evaporation material.