Electrodeposition of Bi_(x)Sb_(2-x)Te_(y) Thermoelectric Films from DMSO Solution

摘要

The electrochemical behavior of nonaqueous dimethyl sulfoxide solutions of Bi~(III), Te~(IV), and Sb~(III) was investigated using cyclic voltammetry. On this basis, Bi_(x)Sb_(2-x)Te_(y) thermoelectric films were prepared by the potentiodynamic electrodeposition technique in nonaqueous dimethyl sulfoxide solution, and the composition, structure, morphology, and thermoelectric properties of the films were analyzed. Bi_(x)Sb_(2-x)Te_(y) thermoelectric films prepared under different potential ranges all possessed a smooth morphology. After annealing treatment at 200 deg C under N_(2) protection for 4 h, all deposited films showed p-type semiconductor properties, and their resistances all decreased to 0.04 OMEGA to 0.05 OMEGA. The Bi_(0.49)Sb_(1.53)Te_(2.98) thermoelectric film, which most closely approaches the stoichiometry of Bi_(0.5)Sb_(1.5)Te_(3), possessed the highest Seebeck coefficient (85 (mu)V/K) and can be obtained under potentials of -200 mV to -400 mV.