Covalent hybrid of hemin and mesoporous carbon as a high performance electrocatalyst for oxygen reduction

A high performance hemin and mesoporous carbon hybrid electrocatalyst for the oxygen reduction reaction (ORR) is developed by using hemin as the Fe–N-containing precursor to control the chemistry of the metal and the chemical composition of the carbon surface. As a first step, Hemin is used as the Fe–N-containing precursor to prepare the Fe–N-doped mesoporous carbon (H-MC) via a nano-casting process by using sucrose as a carbon source and mesoporous silica as a hard template. Hemin is then used as the Fe–N₄-containing precursor to prepare H-MC supported hybrid catalyst. The Fe-doped and N-doped mesoporous carbons are also prepared and the catalytic properties of the prepared catalysts for ORR in alkaline media are investigated. The results show that as compared with the much more expensive Pt/C catalyst, the hybrid catalyst obtained in this work exhibits not only a higher onset potential, but also a higher current density.