Facet-Dependent Activity of Bismuth Bromide Nanosheets in Nonradical Fenton-like Catalysis

Two-dimensional metal oxide nanomaterials with abundantsurfaceactive sites are attractive for Fenton-like catalysis, but the performanceimprovement has been restricted by insufficient knowledge of the materialstructure-activity relationships. One remaining knowledge gapis how the crystal facet determines the catalytic activity in thenonradical Fenton-like oxidation of pollutants. Here, by using bismuthbromide (BiOBr) nanosheets as an example, we explored the differentcatalytic behaviors of its (010) over its (001) facets through bothexperimental and theoretical analyses. The (010) facet with abundantopen channels allows much stronger binding and electronic interactionof PMS than the (001) facet to favor singlet oxygen (O-1(2)) generation. Consequently, BiOBr-(010) exhibited one-order-of-magnitudehigher bisphenol A degradation kinetics than BiOBr-(010), with a4-fold enhancement in intrinsic activity. Its superior environmentalrobustness for selective pollutant degradation in a complicated watermatrix, good stability during cyclic reactions, and feasibility fortreating real water/wastewaters were also demonstrated. Overall, wedemonstrate facet-dependent catalytic activity of BiOBr in nonradicalFenton-like catalysis and elucidate the catalytic mechanisms, whichmay guide the optimization of metal oxide catalysts to favor moreefficient and selective decontamination applications.