A photothermal system for wastewater disposal and co-generation of clean water and electricity

Since energy crisis and water shortage become critical issues in increasingly industrialized society, solar-assisted water disposal technologies remain a great challenge. This work investigated solar-driven photothermal disposal of wastewater for simultaneous production of clean water and electricity. This strategy relies on an integrated photothermal and photoelectric film composed of Ag/TiO 2 nanoparticles grafted on the surface of carbon nanotubes (CNTs) coated with nickel foam (NF) substrate (Ag/TiO 2 @CNTs@NF). The long-wavelength portion in the solar spectrum was employed for high-quality freshwater generation via solar-driven interfacial evaporation (water evaporation rate at 1.48 kg m −2 h −1 ), with a solar-to-water evaporation efficiency of ~96%. The short-wavelength bands were adsorbed for the simultaneous solar-driven oxidation of organic pollutants (oxidation efficiency to methylene blue of ~94.2%) and the generation of electricity (photocurrent of ~228 μA cm −2 ). Therefore, this integrated system can dispose wastewater while achieve pure water and electricity with high utilization efficiency for solar energy. • A photothermal wastewater disposal system is designed. • The wastewater disposal system co-generates freshwater and electricity. • The wastewater disposal system efficiently utilizes full solar spectrum.