Improving Hydrogen evolution catalytic activity of 2D carbon allotrope Biphenylene with B, N, P doping: Density Functional Theory Investigations

Using a first principles approach, we studied the hydrogen evolution reaction activity of newly synthesized biphenylene and B, N, P decorated biphenylene sheet. hydrogen evolution reaction activity of pristine biphenylene sheet is not encouraging, as it is similar to pristine graphene. The Gibbs free energy and overpotential of P(N) doped on biphenylene sheet are 0.022 (-0.092) eV and 22 (92) mV, respectively. The reported Gibbs free energy and overpotential of Pt are 0.9 eV and 90 mV. Hence doping of P(N) atom on top of biphenylene sheet improves hydrogen evolution reaction activity much better (near to) Pt metal. We analyzed the adsorption mechanism of dopants (B, N, P) and hydrogen with Bader charge analysis and density of states analysis. P and N-decoration on biphenylene sheet change its electronic structure so that one obtains improved hydrogen evolution reaction activity for P and N-doped biphenylene sheet. Furthermore, the stability of N, P decorated biphenylene at room temperature with ab initio molecular dynamics and formation energy near that of biphenylene indicate experimental feasibility. We have compared all our best hydrogen evolution reaction activity results in the reaction coordinate and volcano plots of pristine, B, N, and P-doped BPh sheets. They indicate that P-doped biphenylene is a metal-free, powerful catalyst for hydrogen evolution reaction activities.