3.5 Catalytic activities on ozone decomposition
The catalytic activities of as-prepared MnOx catalysts for ozone decomposition were evaluated at 30°C. As shown in Figure 7, the ozone conversion of all the MnOx decreased with reaction time. Nevertheless MnO2-H2-200 showed a better stability, and its ozone conversion kept above 96% after 12h of reaction. While the conversion dropped to 87% for MnO2, 43% for Mn2O3 and 12% for Mn3O4, respectively. MnO2-H2-200 showed the best performance of ozone decomposition due to the abundant surface oxygen vacancies revealed by O2-TPD and XPS analysis.