Studies of Electrochemistry Properties of F ions in Plating Solution for Tin Free Steel

Electrochemistry action of F ions in the TFS (tin free steel) plating solution was investigated by means of A.C. voltammetry, electrochemical impedance spectrum (EIS) and Mott-Schottky analysis technology.The A.C. voltammetry results showed that F ions have a characteristic of inhibiting the chemical state transition of Cr ions, decreasing the oxide current density of lead alloy and lead oxide anode, and influencing the oxidation and reduction mechanism of lead alloy and lead oxide anode.Polymer for Cr and O ions cluster might be formed under conditions of electric field.In addition, inductive reactance phenomenon was observed on EIS for lead alloy anode in Cr ions solution.The properties of F ions solution were found to eliminate the inductive reactance phenomenon, and increase obviously the conducting ability of Cr ions solution.According to analysis of Mott-Schottky, carrier concentrations of anode materials were increased by being added F ions, and anode of lead alloy and lead oxide exhibited an n-type semiconductive character.