Screening of single-atom catalysts sandwiched by boron nitride sheet and graphene for oxygen reduction and oxygen evolution

Single-atom catalysts possess high chemical activity, but their single-atom active sites are not only directly attacked by the reaction intermediates but also easily drifted from the support. In this work, a series of single-atom catalysts sandwiched by boron nitride sheet and graphene (BN/TM/G) are screened for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) theoretically. The scaling relationships indicate that ΔG∗OH can serve as the descriptor to reflect the catalytic activity of BN/TM/G. Moreover, the volcano plot suggests that BN/TM/G with moderate binding strength of ∗OH (0.5 eV < ΔG∗OH < 1.2 eV) show relatively high ORR and OER activity. When the metals are Co, Mo, Ru, Tc, Mn, Cu, Ni, and Fe, the corresponding BN/TM/G catalysts are screened out for efficiently catalyzing ORR and OER. Especially, BN/Cu/G has the highest ORR activity with overpotential of 0.39 V, which may be attributed to the moderate interaction between Cu atom and BN sheet/graphene. The BN/Mo/G has the highest OER activity with overpotential of 0.52 V. In addition, BN/Cu/G and BN/Mo/G have excellent poisoning-tolerance ability for H2S, SO2, and CO. This work is conducive to provide guidance for designing this kind of sandwich-like electrocatalysts for ORR and OER.