Harnessing solar energy by a self-driven photoelectrocatalytic system for versatile water purification: Radionuclides, organic pollutants and pathogen removal

• A CF/SA cathode is prepared and used in a self-driven PEC for water purification. • CF/SA enables improved interfacial charge transfer and more surface binding sites. • The self-driven PEC system has excellent removal for uranium and sulfamethoxazole. • The self-driven PEC system also shows effective antibacterial properties. • It also functions well under real sunlight and exhibits excellent long-term stability. Water purification technology that can simultaneously remove uranium, degrade organic pollutants, and inactivate pathogenic bacteria is crucial for protecting human health and the environment. In this study, we developed a self-driven photoelectrocatalytic (PEC) system using a sulfamic acid-modified carbon felt (CF/SA) cathode and a TiO 2 nanorod photoanode, both of which were obtained by hydrothermal methods. The system demonstrated excellent water purification performance in complex aqueous environments under sunlight illumination. The CF/SA cathode enabled improved interfacial charge transfer and more surface binding sites for uranium (UO 2 2+ ) adsorption and reduction. In the presence of both UO 2 2+ and sulfamethoxazole, almost 100 % UO 2 2+ was removed within 30 min, and 98.98 % sulfamethoxazole was degraded within 1.5 h. The self-driven PEC system also demonstrated effective antibacterial properties by completely inactivating E. coli within 25 min. Variations in wastewater characteristics, such as ions, pH, and organic concentrations had minimal impacts on the stability of the system. It also functioned well under real sunlight and exhibited excellent stability in long-term operation. This work demonstrated an effective cathode material to enhance the uranium reduction and antibiotics decomposition in a self-driven PEC system and provided a new solution for inactivating aqueous pathogens using sunlight only.