A hydrophilic chitosan cathode enables efficient uranium extraction and sulfamethoxazole degradation in a self-driven photoelectrocatalytic system.

A self-driven photoelectrocatalytic system incorporating a chitosan-modified cathode (CSPEC) was developed for the synchronous removal of uranium (UO₂²⁺) and the antibiotic sulfamethoxazole (SMX) from complex radioactive wastewater, along with solar-powered electricity generation. Compared with pristine CF cathodes, the chitosan-modified cathode achieved 20.4 times faster uranium removal, 11.9 times greater SMX degradation, and enhanced power output. Chitosan modification significantly boosted the hydrophilicity of CF, while the plentiful amino and hydroxyl groups on chitosan enabled the preferential uptake of UO₂²⁺, facilitating its effective reduction. Under simulated sunlight, CSPEC maintained 99.5% UO₂²⁺ removal and 97.8% SMX degradation efficiency, with a bit performance decline over 15 cycles. This study offers a new design concept for high-efficiency cathode materials, facilitating resource recovery from solar-powered treatment of organic uranium-bearing wastewater and promoting the synergy between wastewater remediation and energy production.