Elucidating the role of P on Mn‐ and N‐doped graphene catalysts in promoting oxygen reduction: Density functional theory studies

Abstract The non‐noble Mn coordinated N, P co‐doping graphene materials were investigated theoretically in this work based on density functional theory calculation. The electronic structure is effectively tuned after the introduction of P heteroatom. The moderate d band center and density of states at Fermi energy of MnN 4 ‐P1‐G indicate that it is of modest adsorption ability for these O‐containing intermediates. The rank of adsorption energies of O‐containing intermediates for MnN 4 ‐P1‐G is OH* > 2OH* > OOH* > O* > O 2 * > H 2 O*, whereas the MnN 4 ‐P1‐G favors a four‐electron process instead of two‐electron process. The doping of P on MnN 4 ‐P1‐G can increase the kinetic activity for the rate‐determining step as well as the U lim for MnN 4 ‐P1‐G significantly increases from 0.38 to 0.45 V compared with MnN 4 ‐G. The spin density and magnetic moments of Mn are effectively tuned by d, p hybridization to lower the adsorption energy of OH intermediates (rate‐determining step [RDS]) so as to improve the catalytic activity. It is concluded that the P‐doped MnN 4 catalysts with excellent oxygen reduction reaction activity can be obtained and this study can provide theoretical guidance for the rational design of high‐performance Mn‐based carbon materials catalysts.