Promoting low-temperature oxidative dehydrogenation of propane through oxide–support interaction regulation

Abstract

Oxide–support interaction (OSI) plays a significant role in governing the catalytic performance of metal oxides and their supports. However, the influence of OSI strength on activity and selectivity remains poorly understood. Here, we achieved a tunable OSI strength in a NiO/SiO₂ catalyst, thereby tailoring the catalytic performance of low-temperature oxidative dehydrogenation of propane (ODHP). A moderate OSI establishes a delicate balance between geometric and electronic effects, enabling the exposure of highly selective active sites and promoting efficient propane activation. As a result, the NiO/SiO₂ catalyst with moderate OSI exhibited a C₃H₆ formation rate of 112 mol_C3H6 mol_Ni⁻¹ h⁻¹ with a selectivity of 64% at 280 °C. Mechanistic insights from in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and in situ synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) revealed that a moderate OSI effectively suppresses undesired side reactions of direct C₃H₈ over-oxidation and C₃H₆ secondary oxidation.