Enhanced photocatalytic performance of ZnFe2O4/BiOI hybrid for the degradation of methyl orange.

The ZnFe₂O₄/BiOI hybrid photocatalysts were fabricated by the solvothermal method. The crystalline phase, morphologies composition and optical absorption property of the samples with different ZnFe₂O₄ contents were analyzed utilizing XRD, SEM, PL and UV–vis diffuse reflection spectrum, respectively. The photocatalytic activities of the as-prepared photocatalysts were evaluated by degrading methyl orange (MO) under visible light irradiation. Compared with pure BiOI and pure ZnFe₂O₄ catalyst, ZnFe₂O₄/BiOI hybrid photocatalysts could observably enhance photocatalytic activity and the 5% ZnFe₂O₄/BiOI composite performed the optimal degradation efficiency (81.2%) in 100 min. The kinetic studies indicated that the photo-degradation followed the first-order kinetic reaction model. Free radical trapping tests illustrated that ^·O₂⁻ and h⁺ play the key roles in catalytic reaction. In consequence, the ZnFe₂O₄/BiOI composite can be widely used to treat organic pollutant in wastewater. [ABSTRACT FROM AUTHOR]