Investigation of electrochemical behavior of Fe and Mn ions at the surface of electrode/electrolyte interface using electrochemical impedance spectroscopy

Many studies have been conducted using electrochemical impedance spectroscopy (EIS) in recent decades. This is an accurate detection technique for electrochemical systems based on transmission function analysis between voltage and current. In this research, impedance, admittance, and capacitance of composite graphite electrode are investigated and compared in Mn and Fe ions solutions in sulfuric acid medium. The results indicated lower Fe impedance than Mn and admittance greater than that of Mn, indicating a greater Fe conductivity than Mn. Additionally, higher capacitance of Fe than of Mn was because of higher electric characteristics of Fe as compared to Mn. These techniques have been an alternative for cyclic voltammogram (CV) and mainly help in the quantitative determination of kinetic and transmission parameters. Valuable data are obtained using Electrochemical impedance spectroscopy (EIS). Therefore, it can be concluded that EIS is a detecting technique for describing and evaluating the behavior of intermediary elements at the surface of electrode/electrolyte.