Preparation and characterization ofn-type Bi₂Te₃ thermoelectric nanowire array

Wei Wang ¹, Qinghua Huang ¹,Falong Jia¹, Jianzhong Zhang ²

¹Dept.of Applied Chem., School of Chem. Eng. and Tech., Tianjin University , Tianjin300072, P. R. China

²TianjinInstitute of Power Sources, Tianjin 300381, P. R. China

The figure of merit can be improved greatlythrough reducing the size of thermoelectric materials into low dimension, andthe studies on low dimensional thermoelectric materials have brought widely attentionin the world. In our lab, N-typeBi₂Te₃ thermoelectric materials with nanowire arraystructure have been prepared by liquid electrodeposition in the solutionscontaining Bi⁺³ and HTe₃^-1 with alumina porousfilm as template. The electrochemical measurements show that the existence ofBi⁺³ in the solution can accelerate the electrodepositing rate ofTe. N-type Bi₂Te₃ thermoelectric materials can beelectrodeposited into the nano-pores of alumina template in a relatively widepotential range, and their thermoelectric performance are also different withthe change of electrodepositing potential. ESEM and TEM analyses show that thenanowires fill the nanopores of the template uniformly, and their diameter andlength are about 40nm and 50µm separately.