PC@PPy porous membrane prepared by breath figure method with superior mechanical property for efficient solar interfacial evaporation

Solar interfacial evaporation (SIE) is one of the most prospective solar energy harvesting technologies for solving the scarcity of freshwater resources. Herein, we report a novel photothermal membrane polycarbonate (PC) @polypyrrole (PPy) (PC@PPy) adopting to breath figure method followed by surface chemistry modification, and assemble a double-layer solar interfacial evaporator consisting of PC@PPy photothermal membrane as the upper layer and plant fiber-wrapped expanded polyethylene (EPE) foam as the bottom layer for SIE. Due to the abundant porous structure and strong light absorption of the PC@PPy membrane, excellent insulation of the EPE sponge, the as-prepared PC@PPy-EPE evaporator exhibits a high evaporation of 1.78 kg m-2h- 1 and photothermal conversion efficiency of 93.57%, and outstanding evaporation stability and resistance in 16% wt NaCl with an evaporation of 1.58 kg m-2h- 1 under 1 sun irradiation. Moreover, the PC@PPy photothermal possess superior flexibility and strong mechanical properties. Coupling with cost-effective, environment-friendly, simple and easily scale-up breath figure preparation method, the PC@PPy-EPE generator has broad application prospects in SIE.

Automated summary

Researchers report a novel photothermal membrane PC@PPy using the breath figure method and surface chemistry modification for solar interfacial evaporation (SIE). The double-layer SIE device consists of PC@PPy as the upper layer and plant fiber-wrapped EPE as the bottom layer, demonstrating high evaporation rate, excellent stability, and resistance against salt solutions. The cost-effective and scalable PC@PPy-EPE generator shows great potential in SIE.