Work

Tri‐Coordinated Boron Species in Confined Boron Oxide Catalysts for Enhanced Low‐Temperature Oxidative Dehydrogenation of Propane

Year: 2025

Type: article

Abstract: Boron‐based catalysts exhibit great potential for oxidative dehydrogenation of propane (ODHP) to produce olefins. The straightforward synthesis of confined boron‐based catalysts commonly using H 3 BO 3 is intractable because of its abundant hydroxyl groups easily interacting with the supports in a spatially nonselective manner. Herein, we managed to construct a confined BO x @SiO 2 catalyst showing an impressive low‐temperature (400 °C) activity. This catalyst was prepared via the encapsulation of BN nanosheets by SiO 2 shell and subsequent oxidization steps. The in situ generated boron–oxygen species were anchored to silica shells via B─O─Si and hydrogen bonds. BO x @SiO 2 exhibited a unique catalytic behavior of propane conversion uprush, increasing from 5.3% at 410 °C to 28.4% at 424.6 °C for ODHP reaction. That was attributed to the efficient activation of propane triggered by the newly formed tri‐coordinated B─OH (B[3] a and B[3] b ) active sites from the dispersion of molten BO x species in confined SiO 2 . Ab initio molecular dynamics (AIMD) simulations revealed that in the confined structure, the bond angles of O─B─O and B─O─B and system disorder of BO x species increased significantly in molten state, favoring the dispersion of BO x species and formation of B─OH groups, which drove the uprush of propane conversion.

Source: Angewandte Chemie International Edition

DOI: 10.1002/anie.202507525