Optimization of Thermoelectric Properties of p-type AgSbTe2 Thin Films via Electrochemical Synthesis

Silver antimony telluride (AgSbTe2) thin films were fabricated by a simple and cost-effective electrodeposition method for the first time. To investigate the effects of crystallinity and composition on the films’ thermoelectric (TE) properties, amorphous AgxSbyTez solid solutions of various compositions were electrodeposited by tailoring the [Ag+] concentration in the electrolytes, followed by a thermally driven solid-state amorphous-to-nanocrystalline phase transition. Because of the lower carrier concentration in the nanocrystalline phases, higher Hall mobility and Seebeck coefficients, almost twice as high as those observed in the bulk materials, resulted in enhanced power factors of 90–553 μW/mK2. The maximum power factor was obtained from stoichiometric AgSbTe2 thin films. The reported power factors are highly comparable to other values reported for electrodeposited p-type V–VI compounds. The improvement achieved in the TE properties of electrodeposited AgSbTe2 thin films demonstrates the feasibility of the use of these films as p-type legs in room-temperature operations.