Studies on the electrochemical reduction processes of HTeO2 + by CV and EIS

Electrochemical characterizations of the underpotential deposition of tellurium on Au substrate were investigated by cyclic voltammetry (CV) in this paper. The results showed that the irreversible underpotential deposition of Te could take place once the Au electrode was immersed into the HTeO2 + solution. The redox behaviors of adsorbed HTeO2 + were also studied and the results revealed that HTeO2 + could only adsorb on Au electrode surface. The kinetics relating to the reduction of adsorbed HTeO2 + could be affected by HTeO2 + concentration but the charge consumed by the reduction of adsorbed HTeO2 + was concentration-independent. Electrochemical impedance spectroscopy (EIS) analyses about the bulk formation process of Te0 indicated that during the bulk reduction of HTeO2 + to Te0, four electrons were not obtained simultaneously in only one electrochemical step, some intermediate products, which need to be further detected and investigated in the future researches, might emerged in the intermediate processes.