Structure study of bulk nanograined thermoelectric bismuth antimony telluride.
The microstructures of bulk nanograined p-type bismuth antimony telluride with a thermoelectric dimensionless figure-of-merit ZT = 1.4 are investigated using transmission electron microscopy. It is found that the bulk material contains both nano- and microsized grains. Between the nanograins, bismuth-rich interface regions with a 4 nm thickness were detected. In addition, nanoprecipitates as well as other defects are also found to be embedded in the nanograins. The high ZT is attributed to the slight increase in the electrical conductivity, and to the large decrease of the thermal conductivity.
Lan
Yucheng
Y
Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Poudel
Bed
B
Ma
Yi
Y
Wang
Dezhi
D
Dresselhaus
Mildred S
MS
Chen
Gang
G
Ren
Zhifeng
Z