The effect of interstitial boron on the mechanisms of acetylene hydrogenation catalyzed by Pd6: A DFT study

Abstract

Detailed DFT calculations of C2H2 hydrogenation on Pd6, Pd6+ and Pd6B clusters were performed to explore the effect of interstitial B on the mechanisms of C2H2 hydrogenation catalyzed by Pd6. The results show that the Pd6B cluster has the lowest diffusion barriers of H atoms and dissociated barriers of H2; the interstitial B atom can simultaneously improve both the activity and selectivity of C2H2 hydrogenation to C2H4 on Pd6 cluster by altering the major product and the optimal pathway. Moreover, the higher charge is conducive to enhancing the adsorption of C2H2 and C2H4, rather than the selectivity of C2H4 formation. Our work provides some insight into the activity selectivity charge relationship of Pd-based catalysts in C2H2 selective hydrogenation.