The effects of transition metal in Sn-based pyrochlores on the methane catalytic combustion

Abstract

Lanthanum stannate pyrochlores, La₂Sn₂O₇ and La₂SnMO₇(M = Mn, Fe, Co, Ni, Cu), were successfully prepared by citric acid method and confirmed by XRD. TG and TPR characterizations showed that the introduction of transitional metals resulted in significant impacts on the structures and redox performances of prochlores. All the selected transitional metals could significantly improve their methane catalytic combustion performance. Among the doped pyrochlores, La₂SnCoO₇ pyrochlore possessed optimum activities at low temperatures, and Fe-doped pyrochlore showed highest reactivity for high temperature combustion and was proved to be promising materials for high temperature catalytic combustion. The reactivity differences of La₂SnMO₇ were reasonably attributed to the strong interactions between Sn and transitional metal.

* Supported by the Major State Basic Research Development Program of China (2004CB719500), the National 863 High Technology Project (2001AA324050) and Chinese Academy of Sciences (KZCX3-SW-430)

Keywords:

• methane
• catalytic combustion
• Sn-based pyrochlore
• transition metal

Notes

* Supported by the Major State Basic Research Development Program of China (2004CB719500), the National 863 High Technology Project (2001AA324050) and Chinese Academy of Sciences (KZCX3-SW-430)