Corresponding Author

Rong ZHANG(zhangrong@tyut.edu.cn)


Transition metal-nitrogen co-doped carbon catalysts have attracted significant attention because of their reasonable activity and remarkable selectivity toward oxygen reduction reaction (ORR) as cathodic reaction in fuel cells. However, the role of transition metal in the active sites of the catalysts still is uncertain. In this work, the Cox-Ny/C-T catalysts were prepared with BP2000 as a carbon source, urea (Ur) as a nitrogen source and Co(OAc)2•4H2O as a metal precursor by a simple chemical method. Meanwhile, in order to optimize the ORR activity, the catalysts were synthesized with different amounts of Co and urea, and heat-treated at different temperatures from 600-1000 ℃. SEM, TEM, BET, XRD and XPS techniques were used to characterize the catalysts in terms of structures and compositions, as well as the catalytic active sites. CV and LSV were measured to compare the ORR activity and to obtain the electron transfer number. The peak potential for oxygen reduction was approximately 0.829 V (vs. RHE) on the optimum Co0.13-N0.3/C-800 catalyst in an alkaline electrolyte. The results indicated that Co-N-C was potentially catalytic active site and responsible for the ORR catalytic activity in an alkaline electrolyte. The overall electron transfer number for ORR catalyzed by the optimum Co-N/C catalyst was determined to be 3.7, suggesting that the ORR catalyzed by Co-N/C was a mixture of 2- and 4-electron transfer pathways, dominated by a 4-electron transfer process. Furthermore, the Cox-Ny/C-T catalysts also exhibited excellent methanol tolerance and stability.

Graphical Abstract


Cobalt-based nitrogen-doped carbon catalyst, electrocatalysis;oxygen reduction reaction, catalytic active site, heat-treatment

Publication Date


Online Available Date


Revised Date


Received Date



[1] Calle-Vallejo F, Martínez J I, Rossmeisl J. Density functional studies of functionalized graphitic materials with late transition metals for Oxygen Reduction Reactions[J]. Physical Chemistry Chemical Physics, 2011, 13(34): 15639-15643.

[2] Chen R, Li H, Chu D, et al. Unraveling oxygen reduction reaction mechanisms on carbon-supported Fe-phthalocyanine and Co-phthalocyanine catalysts in alkaline solutions[J]. The Journal of Physical Chemistry C, 2009, 113(48): 20689-20697.

[3] Ikeda T, Boero M, Huang S F, et al. Carbon alloy catalysts: active sites for oxygen reduction reaction[J]. Journal of Physical Chemistry C, 2008, 112(38): 14706-14709.

[4] Lee D H, Lee W J, Lee W J, et al. Theory, synthesis, and oxygen reduction catalysis of Fe-porphyrin-like carbon nanotube[J]. Physical Review Letters, 2011, 106(17): 175502-175505.

[5] Lee K R, Lee K U, Lee J W, et al. Electrochemical oxygen reduction on nitrogen doped graphene sheets in acid media[J]. Electrochemistry Communications, 2010, 12(8): 1052-1056.

[6] Lefèvre M, Dodelet J P. Fe-based catalysts for the reduction of oxygen in polymer electrolyte membrane fuel cell conditions: determination of the amount of peroxide released during electroreduction and its influence on the stability of the catalysts[J]. Electrochimica Acta, 2003, 48(19): 2749-2760.

[7] Liu G, Li X, Ganesan P, et al. Development of non-precious metal oxygen-reduction catalysts for PEM fuel cells based on N-doped ordered porous carbon[J]. Applied Catalysis B: Environmental, 2009, 93(1): 156-165.

[8] Li X G, Liu G, Popov B N. Activity and stability of non-precious metal catalysts for oxygen reduction in acid and alkaline electrolytes[J]. Journal of Power Sources, 2010, 195 (19): 6373-6378.

[9] Li X G, Popov B N, Kawahara T, et al. Non-precious metal catalysts synthesized from precursors of carbon, nitrogen, and transition metal for oxygen reduction in alkaline fuel cells[J]. Journal of Power Sources, 2011, 196 (4): 1717-1722.

[10] Ganesan S, Leonard N, Barton S C. Impact of transition metal on nitrogen retention and activity of iron-nitrogen-carbon oxygen reduction catalysts[J]. Physical Chemistry Chemical Physics, 2014, 16(10): 4576-4585.

[11] Kim D W, Li Q L, Saito N. The role of the central Fe atom in the N4-macrocyclic structure for the enhancement of oxygen reduction reaction in a heteroatom nitrogen-carbon nanosphere[J]. Physical Chemistry Chemical Physics, 2014, 16(28): 14905-14911.

[12] Yan X H, Xu B Q. Mesoporous carbon material co-doped with nitrogen and iron (Fe-N-C): high-performance cathode catalyst for oxygen reduction reaction in alkaline electrolyte[J]. Journal of Materials Chemistey A, 2014, 2(23): 8617-8622.

[13] Srinivasu K, Ghosh S K. Transition metal decorated graphyne: an efficient catalyst for oxygen reduction reaction[J]. The Journal of Physical Chemistry C, 2013, 117(49): 26021-26028.

[14] Zhang H J, Li H L, Li X T, et al. Porolyzing cobalt diethylenetriamine chelate on carbon (CoDETA/C) as a family of non-precious metal oxygen reduction catalyst[J]. International Journal of Hydrogen Energy, 2014, 39(1): 267-276.

[15] Chen J Y, Cui X Q, Zheng W T. The role of trace Fe in Fe-N-doped amorphous carbon with excellent electrocatalytic performance for oxygen reduction reaction[J]. Catalysis Communications, 2015, 60: 37-41.

[16] Qian Y D, Du P, Wu P, et al. Chemical nature of catalytic active sites for the oxygen reduction reaction on nitrogen-doped carbon-supported non-noble metal catalysts[J]. The Journal of Physical Chemistry C, 2016, 120(18): 9884-9896.

[17] Bezerra C W B, Zhang L, Lee K, et al. A review of Fe€“N/C and Co€“N/C catalysts for the oxygen reduction reaction[J]. Electrochimica Acta, 2008, 53(15): 4937-4951.

[18] Thorum M S, Hankett J M, Gewirth A A. Poisoning the oxygen reduction reaction on carbon-supported Fe and Cu electrocatalysts: evidence for metal-centered activity[J]. Journal Physical Chemistry Letters, 2011, 2(4): 295-298.

[19] Lefèvre M, Dodelet J P, Bertrand P. Molecular oxygen reduction in PEM fuel cells: evidence for the simultaneous presence of two active sites in Fe-based catalysts[J]. The Journal of Physical Chemistry B, 2002, 106(34): 8705-8713.

[20] Bashyam R, Zelenay P. A class of non-precious metal composite catalysts for fuel cells[J]. Nature, 2006, 443(7107): 63-66.

[21] Lefèvre M, Proietti E, Jaouen F, etc. Iron-based catalysts with improved oxygen reduction activity in polymer electrolyte fuel cells[J]. Science, 2009, 324(5923): 71-74.

[22] Mo Z Y, Liao S J, Zheng Y Y, et al. Preparation of nitrogen-doped carbon nanotube arrays and their catalysis towards cathodic oxygen reduction in acidic and alkaline media[J]. Carbon, 2012, 50(7): 2620-2627.

[23] Byon H R, Suntivich J, Crumlin E J, et al. Fe-N-modified multi-walled carbon nanotubes for oxygen reduction reaction in acid[J]. Physical Chemistry Chemical Physics, 2011, 13(48): 21437-21445.

[24] Niwa H, Horiba K, Harada Y, et al. X-ray absorption analysis of nitrogen contribution to oxygen reduction reaction in carbon alloy cathode catalysts for polymer electrolyte fuel cells[J]. Journal of Power Sources, 2009, 187(1): 93-97.

[25] Liu G, Li X G, Ganesan P, et al. Studies of oxygen reduction reaction active sites and stability of nitrogen-modified carbon composite catalysts for PEM fuel cells[J]. Electrochimica Acta, 2010, 55(8): 2853-2858.

[26] Gomathi A, Reshma S, Rao C N R. A simple urea-based route to ternary metal oxynitride nanoparticles[J]. Journal of Solid State Chemistry, 2009, 182(1): 72-76.

[27] Zhao C Y(赵灿云), Huang L(黄林), You Y(尤勇), et al. Recycling MF Solid Waste into Mesoporous Nitrogen-Doped Carbon with Iron Carbide Complex in Graphitic Layers as an Efficient Catalyst for Oxygen Reduction Reaction[J]. Journal of Electrochemistry(电化学), 2016, 22(2): 176-184.

[28] Chen C(陈驰), Zhou Z Y(周志有), Zhang X S(张新胜), et al. Synthesis of Fe, N-doped Graphene/Carbon Black Composite with High Catalytic Activity for Oxygen Reduction Reaction[J]. Journal of Electrochemistry(电化学), 2016, 22(1): 25-31.

[29] Liu Z Y, Zhang G X, Lu Z Y, et al. One-step scalable preparation of N-doped nanoporous carbon as a high-performance electrocatalyst for the oxygen reduction reaction[J]. Nano Research, 2013, 6(4):293-301.

[30] Oda K, Yoshio T, Oda K. Preparation of Co-C films by radio-frequency sputtering [J]. Journal of Materials Science Letters, 1990, 9(11): 1319-1321.

[31] Luigi O, Alessandro H A, Monteverde V, et al. Activity of CoeN multi walled carbon nanotubes electrocatalysts for oxygen reduction reaction in acid conditions[J]. Journal of Power Sources, 2015, 278: 296-307.

[32] Rao C V, Cabrera C R, Ishikawa Y. In search of the active site in nitrogen-doped carbon nanotube electrodes for the oxygen reduction reaction[J]. The Journal of Physical Chemistry Letters, 2010, 1(18): 2622-2627.

[33] Kónya Z, Kiss J, OszkóA, et al. XPS characterisation of catalysts during production of multiwalled carbon nanotubes [J]. Physical Chemistry Chemical Physics, 2001, 3: 155-158.

[34] Pels J R, Kapteijn F, Moulijn J A, et al. Evolution of nitrogen functionalities in carbonaceous materials during pyrolysis[J]. Carbon, 1995, 33(11): 1641-1653.

[35] Xu F, Minniti M, Barone P, etc. Nitrogen doping of single walled carbon nanotubes by low energy ion implantation[J]. Carbon, 2008, 46(11): 1489-1496.

[36] Morozan A, Jegou P, Jousselme B, et al. Electrochemical performance of annealed cobalt€“benzotriazole/CNTs catalysts towards the oxygen reduction reaction[J]. Physical Chemistry Chemical Physics, 2011,13(48): 21600-21607.

[37] Yuasa M, Yamaguchi A, Itsuki H, et al. Modifying carbon particles with polypyrrole for adsorption of cobalt ions as electrocatatytic site for oxygen reduction[J]. Materials Chemistry, 2005, 17(17): 4278-4281.

[38] Soin N, Roy S S, Karlsson L, et al. Sputter deposition of highly dispersed platinum nanoparticles on carbon nanotube arrays for fuel cell electrode material[J]. Diamond and Related Materials, 2010, 19(5): 595-598.

[39] Su F B, Tian Z Q, Poh C K, et al. Pt nanoparticles supported on nitrogen-doped porous carbon nanospheres as an electrocatalyst for fuel cells€ [J]. Materials Chemistry, 2010, 22(3): 832-839.

[40] Yang S B, Feng X L, Wang X C, et al. Graphene-based carbon nitride nanosheets as efficient metal-free electrocatalysts for oxygen reduction reactions[J]. Angewandte Chemie(International Edition), 2011, 50(23): 5339-5343.

[41] Byon H R, Suntivich J, Shao-Horn Y. Graphene-based non-noble-metal catalysts for oxygen reduction reaction in acid[J]. Chemistry of Materials, 2011, 23(15): 3421-3428.

[42] Wen Z H, Wang X C, Mao S, et al. Crumpled nitrogen-doped graphene nanosheets with ultrahigh pore volume for high-performance supercapacitor[J]. Advanced Materials, 2012, 24(41): 5610ˆ’5616.

[43] Zhang R, Ma J H, Wang W Y, et al. Zeolite-encapsulated M(Co, Fe, Mn)(SALEN) complexes modified glassy carbon electrodes and their application in oxygen reduction[J]. Journal of Electroanalytical Chemistry, 2010, 643(1-2): 31-38.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.