Pore engineering of an Fe–N–C electrocatalyst to enhance the performance for the oxygen reduction reaction by adding g-C3N4 into polyaniline and cyanamide as a precursor

Abstract

When designing Fe–N–C electrocatalysts as platinum group metal-free catalysts for the oxygen reduction reaction, pore engineering is crucial, in addition to creating active sites. In this study, g-C₃N₄ was added during the pyrolysis process of polyaniline and cyanamide, increasing the density of active sites and pore volume of the final product. The uniform distribution of atoms and relatively high ratio of pores resulted in the unprecedented electroreduction of oxygen through a 4e⁻ pathway in acidic and alkaline media. In 0.1 M KOH solution, the half-wave potential of the modified catalyst (E_1/2 = 0.912 V vs. RHE) was 50 mV more positive than that of a commercial 20% Pt/C catalyst. The durability of the catalyst was also better than that of the commercial Pt/C catalyst in acidic and alkaline media.