Optimization of the amount of Nafion in multi-walled carbon nanotube/Nafion composites as Pt supports in gas diffusion electrodes for proton exchange membrane fuel cells

The Nafion loading in multi-walled carbon nanotube (MWCNT) composites with Nafion used as Pt support in the oxygen reduction reaction (ORR) has been studied. We varied the amount of Nafion in these composites and added a Pt loading of 0.3 mg cm−2 to the catalyst layer. The performance of these electrodes in the ORR was measured with linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), chronoamperometry, inductive coupled plasma (ICP), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). In addition, we compared the performance of the MWCNTs as Pt supports with those of the composites. Our results indicate that the composites are better Pt supports in comparison with MWCNT.