Enhanced Electronic Interaction of BO x -La Species Suppressing Hydrolytic Leaching for Stable and Active Oxidative Dehydrogenation of Propane

Boron-based materials are promising catalysts for the oxidative dehydrogenation of propane (ODHP) but face a challenge in retaining the stability of BO x species against hydrolytic leaching. Herein, we developed a boron-based catalyst possessing graded BO x /LaB x O y /LaB 3 O 6 multi-interfaces derived from LaB 6 via a controlled surface oxidation. Multiple characterizations revealed that the active BO x -La species were hosted within the BO x /LaB x O y /LaB 3 O 6 multi-interfaces, where significant charge transfer between B and La evidenced a strong bonding interaction between outer-layer BO x species and La species. The catalyst exhibited an olefin selectivity of 94.9% with 25.9% propane conversion at 530 °C and demonstrated long-term durability during a 1000 h test under intrinsic propane conversion, with a low deactivation rate constant ( k d = 0.0004 h −1 ) and a slow boron leaching rate of only 0.001 wt% h −1 . DFT simulations revealed that in situ - formed BO x -La species exhibited enhanced hydrolysis resistance in the presence of La, which alleviated the electron deficiency of nearby B and impeded the nucleophilic attack of H 2 O at the B sites. This interfacial electronic interaction preserved the active BO x species and ensured high stability under moisture-containing ODHP conditions, outperforming traditionally impregnated BO x catalysts. This work presents a facile structural design principle for developing highly stable boron-based ODHP catalysts.