Abstract: Bi_2-xSb_xTe₃ thermoelectric films were prepared by potentiostatic electrodeposition. The morphology, structure and composition of the electrodeposited films were investigated by ESEM, XPS,
XRD, and EDS. And the Seebeck coefficients of Bi_2-xSb_xTe₃ thermoelectric films electrodeposited at different potentials were measured. The results indicate that bismuth, antimony and tellurium can
be coelectrodeposited to form Sb doped Bi₂Te₃ compouds Bi_2-xSb_xTe₃ in the solution containing Bi³⁺, HTeO⁺₂and SbO⁺. The doping concentration of Bi_2-xSb_xTe₃
thermoelectric films can be controlled through adjusting electrodeposition potential to affect their thermoelectric properties. The composition of the film electrodeposited at --0.5V is Bi_0.5Sb_1.5Te₃,
and it has the largest Seebeck coefficient of 213μV·K^-1. With the decrease of electrodeposition potential, the crystalline state of Bi_{_2-x}Sb__xTe_₃ film will transform from equiaxed crystal into
dendritic crystal. The study shows that the electrodeposition process can be successfully used to synthesize the thermoelectric films with better properties.

Key words: thermoelectric films, bismuth antimony telluride compounds, electrodeposition, Seebeck coefficient