Study of pyrolyzed hemin/C as non-platinum cathodic catalyst for direct methanol fuel cells

• Published in: Science China. Chemistry Vol. 53; no. 9; pp. 2057 - 2062
• Main Authors: Wang, Qiang, Zhou, ZhiYou, Chen, DeJun, Lin, JianLong, Ke, FuSheng, Xu, GuiLiang, Sun, ShiGang
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science China Press 01.09.2010; Springer Nature B.V
• Subjects: Carbon black; Catalysts; Chemical reduction; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Electrocatalysts; Electrodes; Fuel cells; Hydrogen peroxide; Low temperature; Methanol; Oxygen reduction reactions; Platinum; Rotating disks; Sulfuric acid; non-platinum catalyst; hemin; heme; oxygen reduction; direct methanol fuel cell
• ISSN: 1674-7291; 1869-1870
• DOI: 10.1007/s11426-010-4084-y

Biological reduction of O 2 to H 2 O justifies a serious look at heme as a potential O 2 reduction reaction (ORR) catalyst for low temperature fuel cells. In this study, a novel non-platinum electrocatalyst for ORR was prepared through hemin, which is hydrochloride of heme, supported on Black Pearls 2000 carbon black (Hm-BP) pyrolyzed at 700–900 °C in Ar atmosphere. The physical and electrocatalytic properties of as-prepared catalysts were characterized by TGA, XRD, XPS, TEM, rotating disk electrode (RDE) and rotating ring disk electrode (RRDE). It has found that the catalyst treated at 750 °C (Hm-BP-750) exhibits the best property among the Hm-BP catalysts prepared. The onset potential of ORR on the Hm-BP-750 at 30 °C was measured ca. 0.90 V (vs. RHE) in 0.1 M H 2 SO 4 , and mass current density was reached 15.3 mA mg −1 at 0.75 V. It has revealed that O 2 could be reduced directly to water in a 4e process between 0.9 and 0.83V, and the yield of H 2 O 2 was 0–18% in the potential range of 0.83–0.63 V. This methanol-tolerant catalyst also presents excellent stability in medium-term test of direct methanol fuel cell at 80 °C.