Improved Catalytic Performance of Direct Dehydrogenation of Ethylbenzene by Creating Boron Defects on Phosphorus‐doped Boron Nitride

Abstract

AbstractPhosphorus‐doped boron nitride (PBN) has been confirmed as an effective metal‐free catalyst for the direct dehydrogenation (DDH) of ethylbenzene to styrene. In this paper, we further used barbituric acid as co‐reactant sources to create B defects in both PBN and mesoporous PBN (m‐PBN) materials. The XPS, N2 adsorption‐desorption, UV‐vis DRS, EPR, 11B SS NMR characterizations indicated both the electronic and pore structures of the catalyst with B defects were adjusted. Except for the improvement of mass transfer caused by B defects, DFT calculations showed the increase of electron density in B defects areas could enhance the breaking of C−H in ethylbenzene and the bond‐forming of H−H, which was acted to improve the catalytic activity. The m‐PBN with B defects delivered the styrene production rate of 22.54 mmolST g−1 h−1 and stably run 300 h when in‐situ grown on Al2O3, proving that defect tuning strategy is useful to construct efficient catalysts for styrene production.