The oxidative dehydrogenation of propane with CO2 (CO2-ODP) is a green industrial process for producing propene. Cerium oxide-supported platinum-based (Pt/CeO2) catalysts exhibit remarkable reactivity toward propane and CO2 due to the unique delicate balance of C-H and C[double bond, length as m-dash]O bond activation. However, the simultaneous activation and cleavage of C-H, C-C, and C-O bonds on Pt/CeO2-based catalysts may substantially impede the selective activation of C-H bonds during the CO2-ODP process. Here, we report that the scattered rare metal oxide (SRO x , SR = Ga, In) overlayer on Pt/CeO2 exhibits extraordinary activity and selectivity for the CO2-ODP reaction. With the assistance of Pt, the SRO x -Pt/CeO2 could achieve a propane conversion of 38.13% and a CO2 conversion of 67.72%. More importantly, the selectivity of the product propene has increased from 33.28% to 88.24%, a level that is even comparable to the outstanding performance of currently reported PtSn/CeO2 catalysts. A mechanistic study reveals that the strong affinity of the overlayer SRO x to the propane reduces the barrier of C-H bond activation and balances the C-H cleavage rates and the C-O bond groups, accounting for the excellent selective CO2-ODP performance of SRO x -Pt/CeO2 catalysts. The SRO x -modified Pt/CeO2 strategy offers a novel approach to modulating CO2-ODP, thereby facilitating the highly selective preparation of propene.
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