  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.
