Hysteresis effect of magnetic field on electron transfer processes in electrochemical reaction

Using magnetohydrodynamic electrodes (MHDE), a hysteresis effect of the magnetic field on the electron transfer process in the copper deposition in a CuSO₄ solution with 1 M H₂SO₄ as a supporting electrolyte was examined. MHDE are new type electrodes to analyze electrochemical reactions, utilizing the electrolyte solution flow induced by the Lorentz force which can regulate the flow velocity to enhance the mass transfer of active species, ultimately until the current becomes equal to the reaction current corresponding to the rate of electron transfer. From the experimental results, it was shown that the reaction current observed gives a larger value at the first stage of the reaction. However, the current decreases and takes two different values depending on the mode how to apply the magnetic field to the electrode system, i.e., decreasing or increasing the magnetic flux density.