Catalytic oxidation of methane over novel Ce-Ni-O mixed oxide catalysts prepared by oxalate gel-coprecipitation

A novel approach for the synthesis of a new type of binary Ce-Ni-O mixed oxide catalysts is reported. The synthesis method involves the homogeneous gel-coprecipitation of oxalate precursor in alcoholic solution followed by calcinations in air. The results show that the as-prepared samples have high specific surface area and high component dispersion, exhibiting remarkably high activity in the catalytic combustion of methane as compared to the catalysts prepared by conventional coprecipitation techniques. It is suggested that the superior catalytic performance of the oxalate gel-coprecipitated Ce-Ni-O mixed oxide catalysts could be attributed to the generation of highly dispersed NiO x species and the creation of highly active oxygen vacancies as a consequence of an easier incorporation of Ni 2þ ions into ceria lattice by the formation of solid solution in the mixed oxide samples