Ethylene glycol was studied as an electrolyte for the electrodeposition of thermoelectric bismuth telluride films by cyclic voltammetry, rotating ring disk electrode and electrochemical quartz crystal microbalance (EQCM). The reduction of both Bi3+ and Te4+ ions proceeds in one step without the formation of intermediates at potentials more negative than +0.2 V and +0.55 V vs. SHE, respectively. The diffusion coefficients and the rate constants for reduction were found to be similar for Bi and Te. Stoichiometric Bi2Te3 films with a uniform composition profile were obtained from solutions containing up to 1 M of Bi(NO3)(3) and TeCl4, at current densities up to 5 A dm(-2) (similar to 102 mu m h(-1)). Both p- and n-type bismuth telluride films could be obtained, as confirmed by Seebeck coefficient measurements. (C) 2012 Elsevier Ltd. All rights reserved.