Effect of carbonization temperature on bimetallic FeCo-N/C nanofiber electrocatalysts for oxygen reduction reaction in sulfuric acid solution

Polyacrylonitrile (PAN)-based nitrogen-doped carbon nanofibers (NFs) were successfully synthesized by electrospinning technique in combination with impregnation of FeCo-containing solutions and subsequent heat treatment process. Interestingly, the temperature of heat treatment played an important role in fabricating the morphology which could further affect the oxygen reduction reaction (ORR). When the carbonized temperature was 900 °C, the FeCo-N/C NFs catalyst exhibited a comparable catalytic activity for oxygen reduction reaction (ORR) in 0.5 M H2SO4 electrolyte as commercial 20% Pt/C catalyst. The excellent catalytic activity may be attributed to the defect structure, high N content, and high proportional of pyridinic-N, quaternary-N and metal nitrides.