Comparative study of the electrochemical preparation of Bi2Te3, Sb2Te3, and (BixSb1−x)2Te3 films

Abstract In this paper, the processes associated with the electrodeposition of bismuth antimony telluride thermoelectric films, were reported along with an analysis of the composition and crystallinity of the resulting films. The electrodeposition can be described by the general reaction 2(1−x) Bi3++2x Sb3++3 Te+IV+18e−→(Bi1−xSbx)2Te3. Cyclic voltammetry studies led to the determination of the deposition potential of the binaries systems Bi–Te, Sb–Te, and the ternary Bi–Sb–Te dissolved in 1 M perchloric acid and 0.1 M tartaric acid. The influence of the deposition potential and the electrolyte composition on film stoichiometry and their crystal parameters have been studied. It was shown that all stoichiometries of the solid solution BixSb2−xTe3 can be easily adjusted by controlling the deposition potential and the electrolyte solution.