Low-temperature oxidation of hexagonal boron nitride during oxidative dehydrogenation reactions

Abstract

The low-temperature oxidation of hexagonal boron nitride (h-BN) during oxidative dehydrogenation of propane (ODHP) is investigated using a combination of experimental techniques and theoretical modeling. This study explores the role of gas-phase radicals, such as n-propyl and hydroxyl radicals, in initiating the oxidation process, leading to the formation of oxygen-functionalized h-BN edges. Using ab initio molecular dynamics (AIMD) and density functional theory (DFT) calculations, we reveal the mechanism of h-BN oxidation, including hydrogen abstraction, molecular oxygen adsorption, and nitrogen oxide desorption. Experimental results confirm that oxidation occurs only in the presence of both oxygen and propane, demonstrating a critical dependence on reactor geometry on gas-phase radical generation. The oxidation process leads to the incorporation of oxygen into h-BN, forming boron oxyhydroxide phases that influence catalytic activity. These findings provide new insights into h-BN behavior under ODHP conditions and offer guidance for optimizing boron-based catalysts for selective alkane dehydrogenation.