Antiexfoliating h-BN⊃In<sub>2</sub>O<sub>3</sub> Catalyst for Oxidative Dehydrogenation of Propane in a High-Temperature and Water-Rich Environment
Lei Cao, Pu Yan, Sheng Wen, Wenda Bao, Yilan Jiang, Qing Zhang, Na Yu, Yue Zhang, Kecheng Cao, Pengcheng Dai, Jin Xie
Abstract
Hexagonal boron nitride (h-BN) is regarded as one of the most efficient catalysts for oxidative dehydrogenation of propane (ODHP) with high olefin selectivity and productivity. However, the loss of the boron component under a high concentration of water vapor and high temperature seriously hinders its further development. How to make h-BN a stable ODHP catalyst is one of the biggest scientific challenges at present. Herein, we construct h-BN⊃ x In 2 O 3 composite catalysts through the atomic layer deposition (ALD) process. After high-temperature treatment in ODHP reaction conditions, the In 2 O 3 nanoparticles (NPs) are dispersed on the edge of h-BN and observed to be encapsulated by ultrathin boron oxide (BO x ) overlayer. A novel strong metal oxide–support interaction (SMOSI) effect between In 2 O 3 NPs and h-BN is observed for the first time. The material characterization reveals that the SMOSI not only improves the interlayer force between h-BN layers with a pinning model but also reduces the affinity of the B–N bond toward O • for inhibiting oxidative cutting of h-BN into fragments at a high temperature and water-rich environment. With the pinning effect of the SMOSI, the catalytic stability of h-BN⊃70In 2 O 3 has been extended nearly five times than that of pristine h-BN, and the intrinsic olefin selectivity/productivity of h-BN is well maintained.