In Situ Generated Boron Peroxo as Mild Oxidant in Propane Oxidative Dehydrogenation Revealed by Density Functional Theory Study

Yuchen Liu; Ziyi Liu; Wen-Duo Lu; Dongqi Wang; An-Hui Lu

doi:10.1021/acs.jpclett.2c03341

In Situ Generated Boron Peroxo as Mild Oxidant in Propane Oxidative Dehydrogenation Revealed by Density Functional Theory Study

J Phys Chem Lett. 2022 Dec 22;13(50):11729-11735. doi: 10.1021/acs.jpclett.2c03341. Epub 2022 Dec 13.

Authors

Yuchen Liu¹, Ziyi Liu¹, Wen-Duo Lu¹, Dongqi Wang¹, An-Hui Lu¹

Affiliation

¹ State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory for Catalytic Conversion of Carbon Resources, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.

PMID: 36512686
DOI: 10.1021/acs.jpclett.2c03341

Abstract

Boron-based materials catalyzing oxidative dehydrogenation is emerging as a promising protocol for efficient conversion of light alkanes to olefins, while the origin of its remarkable selectivity remains unclear. By means of density functional theory calculations, this work addresses the crucial role of boron peroxo as the mild oxidant in propane ODH: (1) Surface boron peroxo species can be generated in situ in the presence of peroxo species, preferably at the >B-O-B< sites of the zigzag edge, and show high activity to dehydrogenate propane (ΔG^⧧ = 13.5 kcal/mol, ΔG = 8.9 kcal/mol). (2) The >B-O-O· site shows high discriminability of secondary H over primary H of the propane molecule, leading to significantly higher yield of iso-propyl (CH₃ĊHCH₃) than n-propyl (CH₃CH₂ĊH₂); thus, propene formation is favored over deep oxidation. This provides physical insights into the origin of the remarkable olefin selectivity in the boron-containing ODH catalytic systems.