Hydrostatic pressure effect on double layer capacity of iron

The effect of deep sea hydrostatic pressure on double layer capacity still remains unknown. In this study, a novel method to characterize the double layer capacity was put forward. Combining with the potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) experiments under different hydrostatic pressures, it was found that pressure increased the capacity both in diffuse layer and Stern layer, which induced the increase of the current density of both oxidation and reduction reaction near the equilibrium potential.