New insights into electronic structure effect of the SnMnOx nanorod catalysts for low-temperature catalytic combustion of o-dichlorobenzene.

Abstract

For the catalytic combustion reaction of chlorinated volatile organic compounds (CVOCs), the electronic structure of the catalyst surface are important factors in determining the activity, selectivity, and chlorine-resistance stability. Herein, a series of SnMnOx catalysts for the catalytic combustion of CVOCs were prepared by the changing of Sn-doping way to regulate the electron valance state of Mn element, including reflux (R-SnMnOx), co-precipitation (C-SnMnOx) and impregnation (I-SnMnOx). It was discovered that the R-SnMnOx catalyst had better activity and chlorine resistance than the R-MnOx, C-SnMnOx and I-SnMnOx catalyst, and the doping ways of Sn in MnOx catalyst could regulate greatly the surface acidity, active oxygen species, the chemical state of Mn&+ species, and redox ability. Especially, the R-SnMnOx catalysts exhibit excellent water resistance, and the reasons were related to the strong interaction of Sn&+ and Mn&+, which could promote obviously the dispersion of active Mn species, form a large number of acid sites, provide the abundant lattice oxygen species, and own the excellent redox ability, which accelerate the rate of charge transfer between Sn&+ and Mn&+ (Sn4++Mn2+→Sn2++Mn4+) to produce the abundant active species and accelerate the rapid conversion of benzene and intermediates conversion.