posted on 2024-12-12, 15:15authored byChi Zhang, Jinyan Xiao, Jiajian Gao, Xuan Pang, Lei Yang, Shengwei Tang, Yunfa Chen, Wenxiang Tang
Improving the catalyst performance for the thermal oxidation
reaction
faces the daunting challenge of the activity–stability trade-off.
Herein, an evolved heterointerface was constructed on spherical Mn2O3 nanocatalysts to achieve exceptional stability
while maintaining adequate activity by simply introducing La. The
generation of the active Mn3O4–Mn2O3 heterointerfaces by La doping was experimentally
observed, which further segregates to the surface during thermal aging
and forms epitaxially grown heterostructured LaMnO3–Mn2O3 with Mn atoms. The former can act as highly
active sites for the deep oxidation of VOCs due to the richness in
oxygen vacancies and Mn4+ ions, while the latter acts as
the diffusion barrier to inhibit grain growth and produce advantageous
reactive electronic structures around the interface. The La-modified
Mn2O3 oxide reached 90% conversion in toluene
oxidation at 286 °C under the high WHSV of 240,000 mL g–1 h–1 and slightly increased to 327 °C after
thermal aging at 800 °C. This work provides a versatile strategy
for fabricating effective oxidation catalysts with high low-temperature
activity and antisintering properties for industrial applications.