Simultaneously uranium reduction and organics degradation by a drivingpowers enhanced photocatalytic fuel cell based on a UiO-66-NH2 derived zirconia/N-dopped porous carbon cathode

Abstract

Unavoidable organics in uranium wastewater or contaminated waters derive great challenges to traditional uranium removal techniques. Here, a drivingpower enhanced photocatalytic fuel cell (DEPFC) is designed by using a carbon felt (CF)-based UiO-66-NH2 derived zirconia (ZrO2)/N-doped porous carbon (ZrON-C/CF) cathode and a monolithic photoanode, composing of a front FTO glass-based BiVO4 film and a rearmounted Si photovoltaic cell, for effectively oxidizing organics and simultaneously reducing UO22+ from complex wastewater under sunlight illumination. The water contact angle measurements demonstrate that ZrO2 can improve the hydrophilia of cathode thus increases the contact between UO22+ and cathode. The density functional theory indicates that N-doping can enhance the electronegativity of cathode and increases UO22+ adsorption. Meanwhile, the enhanced UO22+ reduction facilitates the charge separation in BiVO4 film, therefore enhancing the organic oxidation. Consequently, under AM 1.5 illumination, the designed DEPFC can remove almost 100% of UO22+ and simultaneous degrade 99% organics within 40 min