Development of advanced catalytic layer based on vertically aligned conductive polymer arrays for thin-film fuel cell electrodes

• Vertically aligned PPy NWs were employed as the ordered catalyst supports.
• PtPd-PPy electrode without additional proton conducting ionomer.
• PtPd-PPy show better mass-transfer than that of commercial Pt/C based electrode.

The degradation of carbon supports significantly influences the performance of proton exchange membrane fuel cells (PEMFCs), particularly in the cathode, which must be overcome for the wide application of fuel cells. In this study, advanced catalytic layer with electronic conductive polymer–polypyrrole (PPy) nanowire as ordered catalyst supports for PEMFCs is prepared. A platinum–palladium (PtPd) catalyst thin layer with whiskerette shapes forms along the long axis of the PPy nanowires. The resulting arrays are hot-pressed on both sides of a Nafion® membrane to construct a membrane electrode assembly (without additional ionomer). The ordered thin catalyst layer (approximately 1.1 μm) is applied in a single cell as the anode and the cathode without additional Nafion® ionomer. The single cell yields a maximum performance of 762.1 mW cm−2 with a low Pt loading (0.241 mg Pt cm−2, anode + cathode). The advanced catalyst layer indicates better mass transfer in high current density than that of commercial Pt/C-based electrode. The mass activity is 1.08-fold greater than that of DOE 2017 target. Thus, the as-prepared electrodes have the potential for application in fuel cells.