Oxidative dehydrogenation of propane to propene with carbon dioxide catalyzed by PtSn/Ce<sub>1−<italic>x</italic></sub>Zr<italic><sub>x</sub>&

<p indent="0mm">The oxidative dehydrogenation of propane with carbon dioxide (CO₂-ODP) is an energy-saving, efficient, and environmentally friendly process for propene production. However, the development of a high-performance catalyst is the key for its industrialization. Based on the understanding that the catalytic CO₂-ODP involves the simultaneous activation of propane and CO₂ molecules, this work investigates the effect of oxygen defects on the catalytic performance of CO₂-ODP over PtSn/Ce_{1−<italic>x</italic>}Zr<italic>_x</italic>O₂ (<italic>x</italic> = 0, 0.4, 0.5, 0.7 and 1.0) from the perspective of the enhanced CO₂ activation. The results show that the CO₂-ODP reaction catalyzed by PtSn/Ce_{1−<italic>x</italic>}Zr<italic>_x</italic>O₂ follows the Mars-van-Krevelen redox mechanism. In comparison with PtSn/CeO₂, the introduction of Zr leads to the formation of Ce_{1−<italic>x</italic>}Zr<italic>_x</italic>O₂ solid solution in the catalyst, which increases the content of oxygen defects. As a result, the dispersion of Pt, and the ability for the adsorption and activation of CO₂ are increased, thus significantly enhance the catalytic performance for CO₂-ODP. Among them, the PtSn/Ce_0.5Zr_0.5O₂ catalyst shows the most oxygen defects, the highest Pt dispersion, and the best ability for the adsorption and activation of CO₂, so that can supplement the consumed lattice oxygen species over the catalyst during the reaction timely, and promote the redox cycles, resulting in the highest propane conversion (31%). The analysis of the catalyst deactivation indicates that PtSn/Ce_0.5Zr_0.5O₂ shows the best ability for the adsorption and activation of CO₂ to supplement the consumed lattice oxygen species, which not only maintains the redox cycles during the reaction, but also promotes the reverse Boudouard reaction and eliminates the carbon deposition, leading to the highest stability.