Role of cerium dopants in MoVNbO multi-metal oxide catalyst for selective oxidation of ethane☆

Abstract The effect of Ce on the structure of MoVNbCeO multi-metal oxide catalysts and the performance of ethane selective oxidation was investigated. These multi-metal oxide catalysts with superior oxidizability exhibit high catalytic activity, and vanadium acts as the active center for ethane oxidation reaction. The improved catalytic activity is related to the increased V5+ content on the catalyst surface, which results from the enhanced transformation of the electrons between V and Ce. Moreover, Ce effectively promotes oxygen adsorption, activation, and mobility. And the presence of Ce can also prevent MoO3 formation and stabilize the Mo5O14-like structure. In addition, the catalyst with a moderate amount of Ce exhibits outstanding catalytic performance. Especially, the MVN-Ce catalyst with a Ce/V ratio of 0.1 exhibits the best performance: the total selectivity of the catalyst toward C2H4 and CH3COOH is the highest (72%) at the ethane conversion of 31%. Therefore, MoVNbCeO multi-metal oxides are promising candidates for selective oxidation.