Preparation and characterization of n-type Bi2Te3 thermoelectric nanowire array

The figure of merit can be improved greatly through reducing the size of thermoelectric materials into low dimension, and the studies on low dimensional thermoelectric materials have brought widely attention in the world. In our lab, n-type Bi₂Te₃ thermoelectric materials with nanowire array structure have been prepared by liquid electrodeposition in the solutions containing Bi⁺³ and HTeO₂⁺ with alumina porous film as template. The electrochemical measurements show that the co-deposition of elements bismuth and tellurium can take place and the electrodeposition potential of Bi⁺³ is more positive than that of HTeO₂⁺. ESEM and TEM analyses show that the diameter and length of Bi₂Te₃ nanowires are about 50nm and 50 μm separately. The Seebeck coefficient α of the Bi₂Fe₃ nanowire array is about - 188 μ V/K at 307K.