Catalytic combustion of methane over La2TM0.3Zr1.7O7−δ (TM = Mn, Fe, and Co) pyrochlore oxides

La2Zr2O7 and La2TM0.3Zr1.7O7−δ (TM = Fe, Mn, and Co) pyrochlores were investigated as catalysts for methane combustion at moderate-high temperatures. They were prepared by the coprecipitation method and characterized by XRD, DSC, H2-TPR, IR, and N2 adsorption/desorption techniques. The introduction of transition metals strongly influences the Zr–O bond strength, the temperature of pyrochlore phase formation, the redox properties, and crystallite size of pyrochlores. Among the catalysts tested, La2Fe0.3Zr1.7O7−δ gives the highest catalytic activity. The catalytic activities of La2TM0.3Zr1.7O7−δ pyrochlore oxides for methane combustion were mainly dependent on the textural properties (BET area, crystallite size).