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
Vertically-aligned silicon nanowires (SiNWs) are investigated for their use as thermoelectric materials. Using a silver-induced electroless-etching method, SiNWs of varying lengths are prepared, which are expected to have lower thermal conductivities as compared to bulk silicon. A thermal constants analyzer is used to perform the thermal analysis of the SiNWs, and thermal conductivity values are reduced by up to 43%. Theoretical models are then used to explain the quantitative results obtained ...
Author(s): Ci-Ling Pan, Peichen Yu, Rone-Hwa Chou, Ting-Gang Chen
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
A 3D carbon nanotube (CNT) network is explored and how potassium or iodine doping can affect the thermoelectric properties of this network. Through in-situ nanoscaling, this CNT network was combined with polyaniline (PANI) and increased the thermoelectric performance of PANI while maintaining the flexible structure of the 3D CNT network. This composite has one of the lowest thermal conductivities of any reported CNT materials....
Author(s): Dehai Wu, Jikun Chen, Kunlin Wang, Lidong Chen, Qun Wang, Rong Xiang, Xuchun Gui, Xugui Xia, Yanfei Zhou, Zewei Wang, Zhen Li, Zikang Tang