  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.
