Doped boron nitride surfaces: potential metal free bifunctional catalysts for non-aqueous Li-O₂ batteries

The development of novel cathode catalysts is crucial for the practical application of lithium-oxygen (Li-O2) batteries. In this paper, we have evaluated the catalytic mechanism and activity of doped hexagonal boron nitride (h-BN) surfaces as cathode catalysts for nonaqueous Li-O2 batteries. From the free energy diagrams it is evident that the CN doped h-BN surface shows the best catalytic activity among the others and this arises due to its considerably lower oxygen reduction reaction (ORR) overpotential and lower oxygen evolution reaction (OER) overpotential. This is due to the weaker binding of the first product (LiO2) and stronger binding with the inserted Li atom. The computations predict that among the considered doped h-BN surfaces, the CN doped h-BN surface can be an efficient metal-free cathode material for nonaqueous Li-O2 batteries.