Crab Shell-Templated Fe and N Co-Doped Mesoporous Carbon Nanofibers as a Highly Efficient Oxygen Reduction Reaction Electrocatalyst

Crab shell, a cheap and abundant biomass waste, is used as a template for preparing iron and nitrogen co-doped mesoporous carbon nanofibers (Fe/N/meso-CNFs). Impregnation of phenolic resin, triblock copolymer, cyanamide, and ferric chloride inside the nanochannels of crab shell allows simultaneous morphology control of Fe/N/meso-CNFs and Fe/N co-doping after the pyrolysis and removal of crab shell. The Fe/N/meso-CNFs exhibit large surface area, porous structure and accessible active sites. Such structural uniqueness enables Fe/N/meso-CNFs ideal for use as an electrocatalyst. The large surface area and porous structure play an important role in exposing electrocatalytically active sites. As a noble-metal free electrocatalyst for oxygen reduction reaction (ORR), Fe/N/meso-CNFs show onset potential and half wave potential close to Pt/C with the limiting current density even exceeding that of Pt/C in alkaline solution. Additionally, the Fe/N/meso-CNFs also present high tolerance towards methanol poisoning and long-term durability, indicating Fe/N/meso-CNFs can be regarded as a potential substitution for Pt towards ORR in alkaline solution.