Facilitating CO2 dissociation via Fe doping on supported vanadium oxides for intensified oxidative dehydrogenation of propane

Selective oxidative dehydrogenation of propane with CO2 (CO2-ODP) represents a promising pathway of propylene production and CO2 utilization. Presently, vanadium (V) based catalysts are commonly used due to the excellent redox ability originated from the multivalent V. However, the CO2-ODP reaction mechanism remains elusive, limiting the rational design of highly efficient catalytic systems. Herein, we introduced Fe into impregnated V-Al2O3 to build a dual-sites catalyst including Fe and V, achieving a C3H8 conversion at ∼43 % and C3H6 selectivity exceed 80 %. Via regulating the Fe/V molar ratio, we clearly describe that the formation of unique Fe-O-V facilitated the CO2 dissociation. Intrinsically, V is the main active site contributing for C3H8 dehydrogenation while Fe site is responsible for the CO2 dissociation, replenishing lattice oxygen to enhance oxidative dehydrogenation of C3H8. The design of dual-sites catalyst and extraction of molecular understanding provide guidance for the rational development of highly active CO2-ODP catalysts.