Three birds with one stone: Constructing graphene oxide composite membranes to boost solar-driven interfacial...

Solar-powered water-thermoelectric cogeneration technology, with its eco-friendly sustainability and high energy efficiency, provides a novel solution to address water scarcity and energy challenges. However, the synergistic optimization of material performance and cost-effectiveness remains a critical challenge. Herein, in this study, zinc ion (Zn²⁺)-crosslinked carboxylated single-walled carbon nanotube (SWCNTs-COOH) intercalated porous graphene oxide (PGO) membrane (PGO-Zn-CNT) is successfully fabricated by using a cost-effective and eco-friendly static deposition method. By chemically etching GO nanosheets to construct a micro and nanoporous structure and intercalating SWCNTs-COOH between GO layers, the photothermal conversion and evaporation performance are simultaneously optimized. In order to trade off evaporation performance and economy, the PGO-Zn-CNT membrane is perforated macroscopically in the center to enhance the heat convection and thermal mass transfer processes. The PGO-Zn-CNT-1.5 membrane achieves an evaporation rate of 1.75 kg m^-2 h^-1 and a conversion efficiency of 92.12 % under 1 sun irradiation. Moreover, the membrane exhibits excellent removal capabilities for typical pollutants such as organic dyes, heavy metal ions, and antibiotics. The research also leads to the innovative construction of a thermoelectric cogeneration system (TCS), which can generate 125.0 mV under 1 light condition and realize the energy utilization of waste heat. The system achieves 8.6 L m^-2 day^-1 of freshwater with a stable 107.4 mV output in an outdoor test. This work develops a TCS that provides a feasible solution for the realization of hydropower cogeneration in remote areas.