Vitalizing fuel cells with a vitamin: pyrolyzed vitamin B12 as non-precious catalyst for enhanced oxygen reduction reaction
S.T. Chang, C.H. Wang, H.Y. Du, H.C. Hsu, C.M. Kang, C.C. Chen, C.S. Wu, S.C. Yen, W.F. Huang, L.C. Chen, M.C. Lin, and K.H. Chen*
Energy & Environmental Science 5 (2012), 5305-5314
The limited natural abundance and high cost of Pt has been a major barrier in its applications for hydrogen fuel cells. In this work, based on the pyrolyzed vitamin B12 (py-B12/C), it is reported to produce superior catalytic activity in the oxygen reduction reaction (ORR) with an electron transfer number of 3.90, which is very close to the ideal case of 4. The H2–O2 fuel cell using py-B12/C provides a maximum power density of 370 mW/cm2 and a current density of 0.720 A/cm2 at 0.5 V at 70 oC. The long-term stability and high ORR activity of py-B12/C make it a viable candidate as a Pt-substitute in the ORR.