A series of Bi(2-x)Sb(x)Te3 powders were prepared via hydrothermal methods by varying x (x=1.45, 1.50, 1.55, 1.56). These powders were then heavily characterized by XRD, EDS, ICP-AES, TEM, SEM and the TPS technique. A low thermal conductivity was desired, so as to give the highest thermoelectric figure of merit (ZT). It was determined that the highest figure of merit was obtained when x=1.55, which resulted in a value of 1.65 ...
Author(s): Chia-Jyi Liu, Hsin -Chang Lai, Liang-Ru Chen, Yen-Liang Liu
CaMnO3 has been proposed for use in thermoelectric materials, due to its favourable thermoelectric properties. In this article, the effect of doping using bismuth and silicon to replace calcium and manganese respectively has been studied. Important properties of the doped compounds measured include thermopower, thermal conductivity, and electrical resistance. Different amounts of dopant are used, and it was determined that the compound Ca0.98Bi0.02Mn0.98Si0.02O3 has the highest ...
Author(s): Ankam Bhaskar, Chia-Jyi Liu, Ching-Lin Chang, J. J. Yuan
A series of compacted Bi0.5Sb1.5Te3 nanoplatelets are synthesized using hydrothermal methods, followed by cold pressing and sintering at temperatures between 300°C and 380°C. A variety of thermal, mechanical and electrical analyses are then performed on the synthesized nanoplatelets including: TPS technique for thermal conductivity, SEM/TEM/AFM to elucidate the mechanical and physical properties of the nanoplatelets, and the Oxford closed cycle cooler cryostat for measurement of electrical ...
Author(s): Chia-Jyi Liu, Gao-Jhih Liu, Liang-Ru Chen, Yen-Liang Liu
Measurements were carried out to determine the electrical resistivity, thermal conductivity and Seebeck coefficients of a series of Fe-doped misfit-layered oxides (Ca3Co(4-x)Fe(x)O(9+delta) (x=0, 0.05, 0.1, and 0.2)). The thermal conductivity experiments were carried out using a Thermal Constants Analyzer via the TPS technique. XRD was also used to characterize the Fe-doped oxides. Overall, the transport properties of the Fe-doped oxides were studied and it was found that ...
Author(s): Chia-Jyi Liu, Jung-Sheng Wang, Li-Chen Huang
A new application for the transient hot-wire technique for thermal conductivity measurements has been described. It is intended to provide an accurate means of implementation of the method to the determination of the thermal conductivity of solids exemplified by a standard reference ceramic material. Measurements of the transient temperature allows an absolute determination of the thermal conductivity of the solid. The uncertainty achieved for the thermal conductivity is better than ±1%, ...
Author(s): Ahmad Gharleghi, Chia-Jyi Liu, Fei-Hung Lin, Yi-Hsuan Pai, Yu-Hsien Chu, Zong-Ren Yang
