Oxidation of Toluene over Mesoporous MnO₂/CeO₂ Nanosphere Catalysts: Effects of the MnO₂ Precursor and the Type of Support

Abstract

Toluene is the most common volatile organic compound (VOC), and the MnO2-based catalyst is one of the excellent nonprecious metal catalysts for toluene oxidation. In this study, the effects of MnO2 precursors and the support types on the oxidation performance of toluene were systematically explored. The results showed that the 15MnO2/MS-CeO2-N catalyst with Mn(NO3)2·4H2O as the precursor and the mesoporous CeO2 nanosphere (MS-CeO2) as the support exhibited the most excellent performance. To reveal the reason behind this phenomenon, the calcination process of the catalyst precursor and the reaction process of toluene oxidation were investigated by in situ DRIFTS. It was found that the MnO2 precursor and the type of catalyst support could have a large effect on the reaction pathway and the produced intermediates. Therefore, the roles of the MnO2 precursor and the type of support should be key considerations when developing the high-performance MnO2-based toluene oxidation catalyst.

Constructing a core–shell Pt@MnOx/SiO2 catalyst for benzene catalytic combustion with excellent SO2 resistance: new insights into active sites

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“…The XPS patterns and Cd 3d XPS spectra of the as-prepared samples are shown in Figures S4 and S5, respectively. As shown in Figure , the Ce 3d fine spectrum of the sample shows that cerium includes Ce 3+ and Ce 4+ , , and the Ce 4+ /Ce 3+ redox pairs play a very momentous role in the photocatalytic oxidative coupling reaction. As shown in Figure S6, the O 1s spectrum is generally divided into two peaks, labeled O sur and O lat .…”

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