Study of the nonlinear behavior of the electrode-skin interface using silicon and Ag/AgCl electrodes

In this paper, we present the results of experiments carried out with Ag/AgCl and silicon electrodes to study the impedance of the electrode-skin interface. Also, we investigate the effect of nonlinear behavior of electrode-skin interface impedance on harmonics in the interface current. We used some Ag/AgCl and silicon electrodes with different areas to apply a voltage to human forearm in some frequencies and measured the current passing through electrode-skin interface. Then, we used these values to calculate the electrode-body system impedance. Further, the ratio of the second harmonic of the current to its fundamental harmonic is calculated to study the effect of nonlinear behavior of the electrode-skin interface. Finally, we compare the generated harmonics and interface impedance of the Ag/AgCl electrodes with silicon electrodes.