Graphite-polypyrrole coated 316L stainless steel as bipolar plates for proton exchange membrane fuel cells

Abstract

316L stainless steel (SS 316L) is quite attractive as bipolar plates in proton exchange membrane fuel cells (PEMFC). In this study, graphite-polypyrrole was coated on SS 316L by the method of cyclic voltammetry. The surface morphology and chemical composition of the graphite-polypyrrole composite coating were investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). A simulated working environment of PEMFC was applied for testing the corrosion properties of graphite-polypyrrole coated SS 316L. The current densities in the simulated PEMFC anode and cathode conditions are around 3×10 9 and 9×10 5 A·cm 2 , respectively. In addition, the interfacial contact resistance (ICR) was also investigated. The ICR value of graphite-polypyrrole coated SS 316L is much lower than that of bare SS 316L. Therefore, graphite-polypyrrole coated SS 316L indicates a great potential for the application in PEMFC.

Deposition of Vulcan XC-72 Coatings on Stainless Steel Bipolar Plates by Reverse Pulsed DC Voltage Electrophoretic Deposition (EPD) for Fuel Cell Applications

“…Based on the polarization curves, the polarization resistance of the samples can be obtained as: [1] where β a , β c are the Tafel slopes of the anodic and cathodic reactions, respectively. I corr has been defined as the corrosion current density and R p is the polarization resistance (5,11). From the data shown in table 3, it can be see that the sample T1 has a significantly lower I corr , i.e., one order of magnitude smaller than the rest of the SS samples.…”

“…Electronically Conducting Polymers (ECPs) a new type of materials with high redox potential and properties of both metals and polymers (5). Different ECPs have been proposed as coatings for bipolar plates.…”