Preparation, Characterization and Application of Epitaxial Grown BiOBr (110) Film on ZnFeO Surface with Enhanced Photocatalytic Fenton Oxidation Properties

A novel BiOBr photocatalyst was epitaxially grown in situ onto the surface of ZnFeO, a ferroelectric material with a strong polarization effect. The formatted BiOBr/ZnFeO composite (BOB/ZFO) showed excellent photocatalytic degradation performance of tetracycline antibiotics (TCs). One of the composites with ZnFeO content of 10% (BOB/ZFO-10) showed the best properties; the degradation efficiency of TCs upon visible light irradiation for 180 min was 99.2%, which was 3.58 times higher than that of pure phase BiOBr. The functions of ZnFeO are assumed to be such that the addition of this ferroeletric material not only regulated the spontaneous polarization of BiOBr in the process of synthesis, but also resulted in the construction of Z-scheme heterostructures due to the appropriate staggered band structure of BiOBr and ZnFeO. In the presence of ferroelectric material ZnFeO, the local structure of BiOBr may be distorted accordingly, resulting in preferential growth of a (110) crystal facet of BiOBr and enhancement of spontaneous polarization, which promotes the efficient separation of photogenerated electron-hole pairs of ZnFeO and BiOBr, and therefore enhances the redox capacity of the photocatalytic degradation of organic pollutants.