Enhanced interaction of nickel clusters with pyridinic-N (B) doped graphene using DFT simulation

The doping effects of nitrogen or boron atom on the stability of defective graphene supported Ni-n (n = 1-6) clusters were explored using density functional theory (DFT) approaches, while the configurations of pyridinic-B and pyridinic-N doped defective graphene (PBG, PNG) were constructed. The binding energies of Ni-n clusters on doped defective graphene are both higher than that of Ni-n on pristine graphene (PG). It is indicated that the interaction between Ni-n clusters and doped graphene is enhanced. PBG has a stronger interaction with Ni-n clusters than PNG, and shows a more favorable ability to stabilize Ni-n clusters. Further, both PBG and PNG carriers provide sufficient positions for binding Ni atoms. The binding site for Ni-1 and Ni-2 cluster on PBG shifts from the vacancy site to the five-membered ring for Ni-3 - Ni-6 clusters. For the PNG, the defects are the anchoring sites for depositing Nin clusters. According to the Hirshfeld charge analysis, the Ni-n-PBG system shows a different charge transfer way from Ni-n-PNG. (C) 2017 Elsevier B.V. All rights reserved.