Potentiodynamic Polarization and Potentiostatic Polarization Behaviors for Iron in Sulfuric Acid Solution with or without a Magnetic Field

Abstract

The effect of a magnetic field on the cathodic reaction of iron in a sulfuric acid solution is studied. Potentiodynamic polarization curves with or without a 0.4 T magnetic field and potentiostatic polarizations under the intermittent imposing or withdrawing of the magnetic field are used to determine the magnetic field effect on hydrogen evolution reaction(HER). The current density in the Tafel region of the cathodic polarization curve at 0.4T magnetic field is higher than that at 0T. When the iron electrode has been polarized potentiostatically in the cathodic Tafel region after many cycles of imposing and withdrawing the magnetic field, imposing the magnetic field finally causes a decrease of the current and withdrawing the magnetic field causes an increase of the current. If the magnetic field had been applied at the start of the polarization, withdrawing the magnetic field causes a sudden decrease of the current density. The effect of magnetic field on cathodic hydrogen evolution is dependent on the cathodic polarization mode and the test sequence.