Results are presented on addition of novel complexing agents citric acid monohydrate (C6H8O7 center dot H2O) and potassium citrate monohydrate (K3C6H5O7 center dot H2O) in hydrochloric acid aqueous solution. The electrochemical reduction process of Bi-III, Te-IV and Sb-III single ions with complexing agent citric acid monohydrate (C6H8O7 center dot H2O) and potassium citrate monohydrate (K3C6H5O7 center dot H2O) in hydrochloric acid bath was investigated by means of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements separately. The results indicate that the presence of citric acid monohydrate (C6H8O7 center dot H2O) and potassium citrate monohydrate (K3C6H5O7 center dot H2O) not only make the three ions stable coexistence in the solution but also make the deposition potential of the three ions closer to each other. The results were discussed facing co-deposition of Bi-Sb-Te three elements in hydrochloric acid bath to prepare p-type Bi0.5Sb1.5Te3 thermoelectric materials. (C) 2015 The Electrochemical Society. All rights reserved.