Exploring the catalytic efficiency of X-doped (X=B, N, P) graphene in oxygen reduction reaction: Influence of solvent and border effects

X doped graphene surfaces, where X is a heteroatom, are interesting for electrocatalytic applications in fuel cell because active sites are generated on the surface. In this work, a new large size surface is proposed to allow several heteroatoms to be located in positions far from the edge of the graphene sheet. Dispersion terms were introduced in the calculations which are crucial in adsorption processes. Natural charges are analyzed to determine the most active sites. A four-electron transfer mechanism is assumed. The energies calculated for each step of the mechanism reveal that the P-doped or the B-doped surface are the ones that favors the oxygen reduction reaction the most, depending on the media.