Boron Nitride and Oxide Supported on Dendritic Fibrous Nanosilica for Catalytic Oxidative Dehydrogenation of Propane

TL;DR

This study demonstrates that supporting boron nitride on dendritic fibrous nanosilica significantly enhances its catalytic activity, stability, and selectivity for propane oxidative dehydrogenation, leading to higher olefin productivity.

Contribution

It introduces a novel support material (DFNS) for boron nitride catalysts, markedly improving their performance in propane dehydrogenation compared to previous catalysts.

Findings

DFNS/BN shows increased catalytic efficiency and stability.

Boron nitride and oxide are both active catalysts with high surface area support.

Higher selectivity linked to hydrogen-bonded hydroxyl groups on B atoms.

Abstract

In this work, we were able to significantly increase the activity of boron nitride catalysts used for the oxidative dehydrogenation (ODH) of propane by designing and synthesising boron nitride (BN) supported on dendritic fibrous nanosilica (DFNS). DFNS/BN showed a markedly increased catalytic efficiency, accompanied by exceptional stability and selectivity. Textural characterisation together with solid-state NMR and X-ray photoelectron spectroscopic analyses indicate the presence of a combination of unique fibrous morphology of DFNS and various boron sites connected to silica to be the reason for this increase in the catalytic performance. Notably, DFNS/B${}_2$O${}_3$ also showed catalytic activity, although with more moderate selectivity compared to that of DFNS/BN. Solid-state NMR spectra indicates that the higher selectivity of DFNS/BN might stem from a larger amount of hydrogen-bonded hydroxyl groups attached to B atoms. This study indicates that both boron nitride and oxide are active catalysts and by using high surface area support (DFNS), conversion from propane to propene as well as productivity of olefins was significantly increased.