Influence of different cerium precursors on the oxygen vacancies and catalytic capacity of Ce-MnOx for ozone catalyzed decomposition

摘要

A series of different cerium precursor-doped MnOx catalysts were synthesized by hydrothermal method, and the doping amount of cerium was further optimized and used for ozone decomposition. The catalysts were characterized by X-ray diffraction, surface area, X-ray photoelectron spectroscopy, Raman scattering spectroscopy, and N-2 adsorption-desorption measurement. Different cerium precursors doped with manganese oxides had significant effects on the structural properties and ozone catalytic activity of the catalysts. All cerium precursors doped with manganese oxides significantly improved the ozone decomposition activity of the catalyst at high humidity. Manganese oxide doped with ammonium ceric nitrate as precursor had the best degradation effect on ozone.The total gas flow with O-3 concentration similar to 40 ppm was maintained at 1 L/min with relative humidity (RH) 65%, /min and the Ce(NH4)(2)(NO3)(6) doped MnO2 exhibits the best ozone decomposition activity and moisture resistance, the decomposition rate of ozone was 95% after 6 h. The characterization results showed that the good ozone decomposition activity of the catalyst was attributed to the large specific surface area and more active sites. Finally, the decomposition mechanism of ozone on the catalyst surface under dry and humid conditions was discussed.