C48, B24N24, CNT(8, 0) and BNNT(8, 0) as catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER)

Abstract

The capacities and performances of Mn doped nanostructures as nano-catalysts for ORR and OER are investigated. The mechanism of ORR by four-electron reaction is opposite of OER and in fuel cell the change in Gibbs free energy of OER is calculated on various surfaces of catalysts. Results shown that the over-potential of ORR on C48, B24N24 and C nanostructures and BN nanostructures are 1.14, 1.10, 1.05 and 0.99 V. Results indicated that the over-potential of OER on C48, B24N24 and C nanostructures and BN nanostructures are 1.10, 1.05, 0.98 and 0.92 V. Results shown that the ΔGreaction of ORR on C48, B24N24 and C nanostructures and BN nanostructures are −0.68, −0.65, −0.57 and −0.52 eV. Results indicated that the ΔGreaction of OER on C48, B24N24 and C nanostructures and BN nanostructures are −0.38, −0.35, −0.29 and −0.27 eV. The Mn-BNNT(8, 0) with high performances is suggested as new catalysts of ORR and OER reactions by theoretical models.