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Monoclinic Mn₅O₈, spinel Mn₃O₄, and perovskite Mn ₂O₃were prepared by thermal decomposition of MnC₂O₄. The formation of different MnOx species observed by thermogravimetric analysis (TGA) and X-ray diffraction (XRD) measurements showed temperature-dependent phase transformation following the path of MnC₂O ₄$\to$Mn₅O₈$\to$Mn₃O₄$\to$Mn₂O ₃occurring during the heat treatment process. Among these manganese oxides, the MO-1 (Mn₅O₈ ) showed the best light-driven photothermal catalytic performance reaching up to 99% of toluene degradation and 75% of mineralization efficiencies reached within 30 min. Besides, it is found that structural defects decrease with the increase of the calcinated temperature, and the Mn${}^{4+}$/Mn${}^{3+}$active sites and oxygen vacancies play an important role in improving the light-driven photothermal catalytic performance.

ZIF-8 composites with Mn (Mn-ZIF-8 & Mn/ZIF-8) were prepared by two methods for the complete catalytic oxidation of toluene. The results revealed that catalytic activity increased with the increasing content of manganese, and the activities of the two series composites were different from each other. The Mn${}_{0.8}$-ZIF-8 prepared by the methanol thermal method showed the best catalytic performance, which had the lowest T${}_{90}$ of toluene conversion, compared with the series of Mn/ZIF-8 catalysts. The resulting composites were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), thermogravimetric analysis (TG) and X-ray photoelectron spectroscopy (XPS). It was concluded that Mn, as the active species, might partly replace Zn in the frame of Mn-ZIF-8 for the catalytic oxidation of toluene at lower temperatures.