Fe/N/C carbon nanotubes with high nitrogen content as effective non-precious catalyst for oxygen reduction reaction in alkaline medium

The non-precious metal catalysts usually have low nitrogen content, resulting in poor oxygen reduction reaction (ORR) performance. Herein we demonstrated a strategy to synthesize the Fe/N/C carbon nanotubes (Fe–N–BCNTs) with high nitrogen content. The strategy included pyrolysis of ferric chloride and dicyandiamide, polymerization of pyrrole onto intermediate product's surface, and following by calcination in N2 atmosphere. Electrochemical test results show that the catalyst exhibits highly efficient ORR activity with an onset potential of 0.995 V (vs reversible hydrogen electrode) in 0.1 M KOH solution, 30 mV more positive than that of 20 wt. % Pt/C catalyst. The excellent ORR performances could be attributed to the more nitrogen functional groups in Fe–N–BCNTs-PPy-800 catalyst, which is revealed by Raman and XPS. Moreover, the prepared catalyst exhibits better methanol tolerance and higher stability in comparison to commercial Pt/C catalyst.