Fe-Nx doped carbon nanotube as a high efficient cathode catalyst for proton exchange membrane fuel cell

Abstract In this work, we report our recent efforts in developing carbon nanotube cross-linking MOF-derived Fe/N/C catalysts as oxygen reduction electrocatalysts for fuel cell. It is witnessed that the carbon nanotube cross-linking strategy can effectively improve the activity and stability of fuel cell, which can be assigned to its fast and convenient electron conduction channels offered by loosely cross-linked carbon nanotubes. The results of 57Fe Mossbauer spectroscopy show that there are three spin states of Fe-N4 structure in the material, of which low-spin state D1-FeIIN4 and high-spin state D3-N-FeN4 are both considered to be the main active sites of oxygen reduction reaction. For fuel cell, high performance of 0.732 A cm−2 at 0.7 V is reached. The novel cross-linking catalyst sheds light on the development of non-precious metal catalysts for fuel cells.