Synthesis of hollow carbon nanostructures as a non-precious catalyst for oxygen reduction reaction

Carbon-based nanostructures as a non-precious catalyst for oxygen reduction reaction (ORR) exhibit excellent electrocatalytic activities due to high specific surface areas and favorable active sites supported by the doped transition metals and nitrogen species. We synthesize the metal-nitrogen doped carbon nanostructures (MPc-C, M = Fe,Co) by using a template method in the presence of metal phthalocyanine including FePc, CoPc, and FeCoPc as metal and nitrogen as well as carbon sources. The as-prepared carbon nanostructures show a high specific surface area, porous structure, and metal-nitrogen dopants, as observed by field-emission scanning electron microscopy (FE-SEM), field-emission transmission electron microscopy (FE-TEM), X-ray photo-electron spectroscopy (XPS), and nitrogen sorption measurement. Especially, among the doped carbon nanostructures, FeCoPc-C exhibits superior ORR electrocatalytic properties in an alkaline medium: an electron transfer number close to 4, high half-wave potential, improved electrochemical stability, and methanol tolerance.