Corrosion resistance tests
Potentiodynamic and potentiostatic tests were carried out in
a1MH2SO4 þ 2 ppm HF solution at 70 C purged with H2 and O2
using a Bio Logic potentiostat VMP3 to determine the corrosion
resistance of the bare and coated aluminum bipolar plates. A
conventional three electrodes cell system was used. A graphite and
saturated calomel electrode (SCE) was used as the counter and
reference electrode, respectively. The potentiodynamic polarization
curves for coated aluminum were measured over the range,
0.4 Ve0.1 V, at a potential scanning rate of 2 mV s1
. In the case of
bare aluminum, potentiodynamic curve was measured over the
range of 0.1 Ve0.1 V with same scanning rate of coated
aluminum. The potentiostatic curves were measured for 3 h in
0.1 V and 0.6 V, which correspond to the anode and cathode
conditions in PEM fuel cells.