Nafion effect on dual-bonded structure cathode of PEMFC

Hydrophobic and hydrophilic electrodes have inherent problems in proton/gas transport caused by properties of binder material (PTFE or Nafion) in catalyst layer (CL). A novel cathode with dual-bonded CL (hydrophilic/hydrophobic) has been designed and evaluated through testing cell performance. Two groups (hydrophilic/constant hydrophobic CL and constant hydrophilic/hydrophobic CL) of cathodes with the same Pt loading of 0.2 mg cm−2 were fabricated to investigate Nafion content/loading effect on cell performance. For hydrophilic/constant hydrophobic electrodes, cell performance increased from 0.56 W cm−2 to 0.59 W cm−2 when the Nafion content in hydrophilic layer increased from 35 wt% to 55 wt%. Reducing Nafion loading in hydrophobic layer from 0.3 mg cm−2 to 0 mg cm−2, peak power density of constant hydrophilic/hydrophobic electrodes increased from 0.64 W cm−2 to 0.77 W cm−2 at ambient pressure.