MIL-53(Fe)-derived Fe2O3 with oxygen vacancy as Fenton-like photocatalysts for the elimination of toxic organics in wastewater

A series of Fe2O3 nanomaterials with oxygen vacancies were synthesized by pyrolysis of MIL-53(Fe) at different temperatures. Compared with commodity Fe2O3 and Fe2O3 prepared directly from FeCl2 center dot 6H(2)O, 500-Fe2O3 was prepared by MIL-53(Fe) pyrolysis at 500 degrees C and had a smaller particle size, more active sites and a higher oxygen vacancies content. Electrochemical analysis indicated that 500-Fe2O3 had a stronger photoelectric response, lower electrochemical impedance and lower charge recombination rate. The presence of oxygen vacancies increased the photocurrent density and promoted electron transfer and 500-Fe2O3 had better activation properties for persulfate. Activity experiments, X-ray diffraction and Fourier transform infrared showed that 500-Fe2O3 had a wide range of pH adaptation and good catalytic stability. Free-radical trapping experiments and electron paramagnetic resonance analysis confirmed that the main active species in the reaction system was center dot O-2(-) and holes. This study provides a viable solution for improving the performance of the Fe2O3 catalyst. (C) 2019 Elsevier Ltd. All rights reserved.