Nitrogen-doped carbon nanoflower with superior ORR performance in both alkaline and acidic electrolyte and enhanced durability

Three carbon precursors (viz. pyrrole, aniline and phenanthroline) were impregnated in the mesoporous silica nanoflower (MSNF) template, which was found to yield considerable effect on the morphology of the derived carbon materials (NCNF). The derived NCNF catalysts present the excellent ORR performance as the metal-free catalyst. The optimal catalyst, NCNF-PHEN-900, outperform the Pt/C catalyst with 30-mV halfwave potential (E1/2) surpassing in alkaline media, while in the acidic media, NCNF-PHEN-900 (E1/2 = 0.76 V) exhibit a comparable activity to Pt/C, suggesting it one of the best for metal-free catalysts used for ORR.250