Magneto-electrical cyclic voltammetry for visualization of current distribution in the electrolyte

Cyclic voltammetry is widely used in electrochemistry. To visualize the current distribution in the electrolyte, we developed a two-dimensional magnetic imaging system, combining the electric measurement component used in conventional cyclic voltammetry with a pair of MR (magnetic resistive) sensors to detect the x- and y-magnetic components. The resulting system allows simultaneous measurement of the electronic current of the working electrode and the magnetic field resulting from the transport of ions by migration in the bulk electrolyte. The current distribution in the electrolyte was reconstructed using the magnetic field strength data obtained at multiple points. Consequently, we could observe the change in current distribution when changing the length of the working electrode immersed in the electrolyte.