Atomic scandium and nitrogen-codoped graphene for oxygen reduction reaction

• Published in: Journal of power sources 2019-08, Vol.431, p.265-273
• Main Authors: Wen, Xudong, Duan, Zhiyao, Bai, Lu, Guan, Jingqi
• Format: Article
• Language: English
• Subjects: Density functional theory; Nitrogen-doped graphene; Oxygen reduction reaction; Scandium; Single-atom catalysis
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2019.126650

Rational design of highly active and durable electrocatalysts for oxygen reduction reaction is critical to substitute precious metal platinum for fuel cells. Herein, a novel non-precious atomic scandium embedded into nitrogen-doped graphene material is successfully synthesized via a facile annealing method. The catalyst exhibits superior oxygen reduction reaction performance in both 0.1 M KOH and 0.5 M H2SO4, with onset potential (Eonset, 0.99 vs 0.82 V) and half-wave potential (E1/2, 0.89 vs 0.72 V). Theoretical calculations reveal that the possible active sites for ORR might be ScN3O and ScN2O embedded into the N-doped graphene. The outstanding electrochemical stability and strong tolerance to methanol crossover on the atomic scandium and nitrogen-codoped graphene make it a promising application in metal-air batteries and fuel cells. [Display omitted] •Atomically dispersed scandium was embedded onto nitrogen-doped graphene.•Sc@NG shows ORR performance with E1/2 of ∼0.89 V vs RHE in 0.1 M KOH.•Sc@NG shows ORR performance with E1/2 of ∼0.72 V vs RHE in 0.5 M H2SO4.•The active sites for ORR might be ScN3O-Gand ScN2O embedded onto graphene.