Photocatalytic removal of U(VI) from aqueous solution under visible light by bismuth oxyiodide/graphitic carbon...

Applicable to convert soluble U(VI) into the less mobile U(IV) form, the photocatalytic process is widely regarded as an efficient solution to uranium pollution. In the present study, BiOI/g-C₃N₄ (BICN) composites were produced through uncomplicated hydrothermal synthesis, followed by U(VI) photocatalytic reduction. Batch experiments were conducted to demonstrate the exceptional capability of BICN to address uranium contamination. Specifically, the 5%-BICN composite exhibited higher photocatalytic efficiency in U(VI) reduction, with its performance improved by 1.5 times over BiOI and 3.0 times over g-C₃N₄. Characterized by p-n heterojunction, BICN composites enhance the movement and separation efficiencies of photogenerated carriers, which significantly promotes the production of •O₂^- radicals that are critical for U(VI) photocatalytic reduction. These results provide crucial guidance on the potential application of BICN composites in environmental remediation processes.