Abstract
In heterogeneous catalysis, oxygen vacancies of metal oxides play a key
role by modulating properties of coordination, electron states,
electrical conductivity, and surface property. However, the
investigation of oxygen vacancies in nonmetal oxides and their catalytic
applications have rarely been reported. Here, we present oxygen
vacancies-rich BPO4 hollow spheres covered by few-layer hexagonal boron
nitride (BN) with a sandwich-like structure (BN@BPO4@BN) through an
in-situ growth method. The as-prepared catalyst showed better catalytic
activity and higher selectivity than that of commercial BN in the
oxidative dehydrogenation of propane to propene because of the
synergetic effect between oxygen vacancies-rich BPO4 and h-BN. Oxygen
vacancies increase the adsorption amount of propane and the confined
space at the interface of BN and BPO4 weakens the adsorption of propene,
benefiting the recycle of active sites. Moreover, the confined space and
oxygen vacancies result in the transformation of reaction kinetic model.