Boosted visible-light photocatalytic performance of TiO2-x decorated by BiOI and AgBr nanoparticles

Abstract The prominent visible-light-responsive TiO2-x/BiOI/AgBr photocatalysts with p-n-n heterojunctions were synthesized via a mild hydrothermal method, followed by precipitation approach at room temperature. All of the obtained results illustrated that the ternary TiO2-x/BiOI/AgBr nanocomposites act as a highly efficient photocatalysts for different dyes decomposition compared to the TiO2, TiO2-x, and TiO2-x/BiOI photocatalysts. The remarkable visible light photocatalytic performance for the TiO2-x/BiOI/AgBr photocatalysts is ascribed to striking visible-light absorption capability, plenteous active sites, and reinforced charge separation repressed by p-n-n heterojunctions, which were evidenced by optical, textural, and photoelectrochemical characterizations. The TiO2-x/BiOI/AgBr (10%) photocatalyst with considerable reusability exhibited substantial visible-light photoactivity towards RhB, MB, and fuchsine degradations, in which RhB, MB, and fuchsine degradation percentages are 98% (at 60 min), 99% (at 300 min), and 76% (at 300 min), respectively. Additionally, the results of quenching tests suggested that holes and superoxide radicals have a notable character in the degradation process. The strategy to construct these multi-heterojunction photocatalysts can give an innovative perspective to design highly efficient systems for solving environmental pollution crisis using TiO2 under visible light.