Probing the Transformation of Boron Nitride Catalysts under Oxidative Dehydrogenation Conditions
Chemistry, Ames Laboratory
Journal or Book Title
Journal of the American Chemical Society
Hexagonal boron nitride (h-BN) and boron nitride nanotubes (BNNTs) were recently reported as highly selective catalysts for the oxidative dehydrogenation (ODH) of alkanes to olefins in the gas phase. Previous studies revealed a substantial increase in surface oxygen content after exposure to ODH conditions (heating to ca. 500 °C under a flow of alkane and oxygen); however, the complexity of these materials has thus far precluded an in-depth understanding of the oxygenated surface species. In this contribution, we combine advanced NMR spectroscopy experiments with scanning electron microscopy (SEM) and soft X-ray absorption spectroscopy (XAS) to characterize the molecular structure of the oxygen functionalized phase that arises on h-BN and BNNTs following catalytic testing for ODH of propane. The pristine BN materials are readily oxidized and hydrolyzed under ODH reaction conditions to yield a phase consisting of three coordinate boron sites with variable numbers of hydroxyl and bridging oxide groups which is denoted B(OH)xO3-x (where x = 0-3). Evidence for this robust oxide phase revises previous literature hypotheses of hydroxylated BN edges as the active component on h-BN.
American Chemical Society
Love, Alyssa M.; Thomas, Brijith; Specht, Sarah E.; Hanrahan, Michael P.; Venegas, Juan M.; Burt, Samuel P.; Grant, Joseph T.; Cendejas, Melissa C.; McDermott, William P.; Rossini, Aaron J.; and Hermans, Ive, "Probing the Transformation of Boron Nitride Catalysts under Oxidative Dehydrogenation Conditions" (2018). Chemistry Publications. 1097.