We present a detailed study of the evolution of the electrical, galvanomagnetic, and thermodynamic properties of polycrystalline Ag x Mo 9 Se 11 compounds for 3.4 ≤ x ≤ 3.8 at low temperatures (2−350 K). In agreement with density functional theory calculations, the collected data show an overall gradual variation in the transport properties from metallic to semiconducting behavior on going from x = 3.4 to 3.8. The results evidence subtle variations in the electronic properties with the Ag content, typified by both positive and negative phonon-drag effects together with thermopower and Hall coefficient of opposite signs. Analysis of the data suggests that these features may be due to peculiarities of the dispersion of the valence bands in the vicinity of the chemical potential. A drastic influence of the Ag content on the thermal transport was evidenced by a pronounced change in the temperature dependence of the specific heat below 10 K. Nonlinearities in the C p (T 3 ) data are correlated to the concentration of Ag atoms, with an increase in x resulting in a more pronounced departure from a Debye law. The observed behavior mirrors that of ionic conductors, suggesting that Ag x Mo 9 Se 11 for x ≥ 3.6 might belong to this class of compounds.

Bismuth telluride alloy films of uniform thickness have been successfully prepared by electrodeposition from a solution containing Bi3+ and HTe02+ ions in 1 mol dm-3 nitric acid (pH=O) on stainless steel. The electrodeposited films are monophasic and exhibit a polycrystalline structure (R3rn). The film composition is dependent on the electrolyte composition and the current density. The electrical properties of the electrodeposited samples have been determined. The obtained films are n-type semiconductors with high carrier concentration.

Electrodeposition has been used for decades to deposit various semiconductors on targeted surfaces. It is a powerful method for growing thin films and/or nanostructures with potential thermoelectric properties. It has a competitive edge over physical processes due to its cost-effective operation and facilities. This paper furnishes an overview of the evolution of research in the area of electrodeposition of thermoelectric compounds as a function of time and shape category (bulk, wire, and film). Selected results on V 2 VI 3 compounds are organized in a synthetic presentation according to shape. Up-to-date literature coverage is provided, based on over 200 papers and proceedings. In this context, our research group is involved in complementary aspects concerning tailoring electrodeposited film morphology in order to enhance thermoelectric properties. Examples are given dealing with pulse electroplating and nanowires.