Fabrication of Surface-Patterned Membranes by Means of a ZnO Nanorod Templating Method for Polymer Electrolyte Membrane Fuel-Cell Applications

Abstract Surface‐patterned Nafion films were prepared by using different types of ZnO nanorods as templates for polymer electrolyte membrane fuel‐cell (PEMFC) applications. Varying the concentrations of the Zn precursor produced ZnO nanorods with different diameters and pore sizes in the Nafion films. The surface‐tuned structure of the films improved fuel‐cell performance owing to effective Pt loading on the membranes through an enhancement in surface area. Also, the interconnected morphology resulted in a reduction in charge‐transfer resistance at the interface between the electrode and membrane. The optimum surface‐patterned Nafion film recorded a current density of 1.19 A cm −2 at 0.6 V and a maximum power density of 0.95 W cm −2 . These values are much higher than those of non‐patterned Nafion (0.85 A cm −2 and 0.59 W cm −2 , respectively). We expect that the patterning process using ZnO nanorod templates will improve the performance of any electrochemical device by allowing for the tuning of the interfacial resistance.