| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1282451 | International Journal of Hydrogen Energy | 2011 | 12 Pages |
The goal of the present work was to evaluate the corrosion resistance of carbon black (CB)-synthetic graphite (SG)-poly(vinylidene fluoride) (PVDF) composites using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves. The tests were conducted in 0.5 M H2SO4 + 2 ppm HF solution at 70 °C to simulate the typical environment of polymer electrolyte membrane fuel cells. The fracture surface of the specimens was characterized by scanning electron microscopy. The through-plane electrical conductivity was also determined. The corrosion resistance decreased as the carbon black content increased up to 5 wt.%. The highest electrical conductivity was achieved for the composition CB = 5 wt.%, PVDF = 15 wt.%, SG = 80 wt.%. A detailed discussion of the EIS data is given. This approach is unprecedented in the current literature. EIS has proven to be a valuable tool to the design of electrically efficient bipolar plates.
► EIS results correlate with electrical conductivity measurements. ► Corrosion resistance depends on CB content and is inversely proportional to conductivity. ► The electrochemical behavior of the composites was explained by EIS modeling and SEM images.
