Effect of bonding patterns of borides in oxidative dehydrogenation of propane
Abstract
Borides are newly promising catalysts for the oxidative dehydrogenation of propane (ODHP). This study delves into the effect of bonding patterns on the performance of boride catalysts in the ODHP. By contrasting the catalytic behaviors of hexagonal (h-BN) and cubic (c-BN) boron nitride, the superior activity of h-BN is highlighted. At 520 °C, h-BN demonstrates a conversion level of 24.3%, while the c-BN was almost inactive. Comprehensive characterization techniques corroborated h-BN constituted by the sp2-hybridized B-N bond tends to facilitate the formation of active oxygenated boron species during the ODHP reaction, unlike the sp3-hybridized c-BN, which resists oxidative functionalization. Combined with the theoretical calculation, the high energy barrier associated with the cleavage of sp3 B-N bonds is mainly responsible for the inertness of c-BN. Similar trends were observed in boron phosphide samples. The results underscore the importance of bonding patterns and provide implications for the design of efficient ODHP catalysts.