Title :
The effect of various dopants on thermoelectric properties of Bi2(Te0.9Se0.1)3 polycrystals
Author :
Nozue, A. ; Park, Y.H. ; Kawasaki, A.
Author_Institution :
Refrigeration Res. Lab., Matsushita Electr. Ind. Co., Ltd, Kusatsu-City, Japan
Abstract :
In this study, mechanical alloying followed by pulse discharge sintering (MA-PDS) was employed to synthesize the bulk Bi2(Te0.9Se0.1)3 thermoelectric materials and then the compacts were spread by hot-pressing process. The additives we selected several metal iodide and bromide (AgBr, CuBr, CuBr2, AgI). All dopants increase the carrier concentration and power-factor. The excellent metal element of dopants were silver and copper. Moreover, the effect of spreading on the crystal orientation and thermoelectric performance of the compacts was investigated. The microstructural characterizations of the spread compacts by XRD and SEM indicated a high crystallographic orientation after spreading. Furthermore, power-factor and carrier mobility was increased by the high crystal orientation.
Keywords :
X-ray diffraction; bismuth compounds; carrier density; carrier mobility; crystal microstructure; hot pressing; scanning electron microscopy; semiconductor materials; thermoelectric power; thermoelectricity; AgBr; AgI; Bi2(Te0.9Se0.1)3; Bi2(Te0.9Se0.1)3 polycrystals; CuBr; CuBr2; SEM; XRD; carrier concentration; compacts; crystal orientation; dopants; hot-pressing process; mechanical alloying; power-factor; pulse discharge sintering; thermoelectric performance; thermoelectric properties; Additives; Alloying; Bismuth; Copper; Crystal microstructure; Crystallography; Silver; Tellurium; Thermoelectricity; X-ray scattering;
Conference_Titel :
Thermoelectrics, 2003 Twenty-Second International Conference on - ICT
Print_ISBN :
0-7803-8301-X
DOI :
10.1109/ICT.2003.1287442
