The key role of metal dopants in nitrogen-doped carbon xerogel for oxygen reduction reaction

High active non-precious catalysts doped with various transition metal species are prepared to elucidate the effect of transition metals. Metal doping evidently promote the formation of micropores, mesopores, and pyridinic-N. NCX doped with iron exhibits the greatest ORR activity possibly due to the formation of graphitic structures and the enhanced quaternary-N contents. The total N contents do not determine ORR activity, and the synthesis affects which from the interaction of the metals with nitrogen and carbon atoms, that have important functions in achieving high ORR activity.208