Decoupling size and electronic effects of Pt through oxygen vacancy engineering in propane dehydrogenation

Supported-metal catalysts are well-established for industrial catalysis, but controlling the metal-oxide interaction (MSI) is challenging because of the intricate geometric and electronic effects. Herein, this paper describes the strategy of controlling metal-oxide interaction by pre-tailoring the oxygen vacancy (O v ) concentrations on defective metal oxides for supported Pt catalysts. ZnO distinguishes itself among the metal oxides examined, with the structural and chemical attributes of O v playing a pivotal role in determining its effectiveness. At lower O v concentration (less than 0.82 mmol/g ZnO ), the O v in defective ZnO x impedes Pt growth, while higher O v concentration (0.82 to 5.63 mmol/g ZnO ) induces an electron-sufficient Pt state without compromising Pt dispersion. During propane dehydrogenation (PDH), performed under reducing conditions, the optimized Pt/ZnO x achieved 44% of propane conversion and 90% of propylene selectivity at 600 °C under 4 h −1 of C 3 H 8 , which is comparable to that of PtSn/Al 2 O 3 analogue. This oxygen vacancy engineering strategy provides mechanistic insights into disentangling geometric and electronic factors, advancing the rational design of MSI-controlled PDH catalysts.