Preparation of nitrogen-doped porous carbon modified by iron carbide and its application in an oxygen reduction reaction

A high-efficiency carbon-based metal catalyst was prepared using inexpensive raw materials and a simple synthetic method to replace the commercial platinum-based catalyst in oxygen reduction reaction (ORR). In this article, clay was used as the template, and residual organic matter after oil adsorption was used as the carbon source and the nitrogen source, respectively. Through ion adsorption, nitrogen-doped porous carbon catalyst (Fe3C/NC) modified by iron carbide was synthesized by high-temperature pyrolysis and etching of clay mineral template. Fe3C/NC was characterized by Fourier-transform infrared spectroscopy (FT-IR), High-resolution transmission electron microscopy (TEM) and X-ray diffractometer. Further experiment showed that this catalyst had good electrochemical activity for ORR.Graphical abstractIn this paper, we use the organic matter in the waste clay as the carbon source and nitrogen source and use the characteristics of clay in the waste clay to introduce iron ions into the reaction. After high-temperature calcination, we get Fe3C/NC composite. Fe-N co-doping can expose more graphite defects and more active sites, which can also improve the electrocatalytic performance of ORR.