期刊
JOURNAL OF APPLIED PHYSICS
卷 114, 期 4, 页码 -出版社
AMER INST PHYSICS
DOI: 10.1063/1.4817074
关键词
-
资金
- National Natural Science Foundation of China [11174292, 51101150, 50972146, 10904144]
(Bi2Te3)(0.2)(Sb2Te3)(0.8) (BST) based nanocomposites dispersed with amorphous SiO2 (a-SiO2) nanoparticles (similar to 50 nm) were fabricated and their thermoelectric properties were investigated in the temperature range from 293 K to 490 K. The results indicate that with increasing volume fraction of a-SiO2 from f = 0 to 0.55, 1.10, and then to 2.20 vol. %, the electrical resistivity rho of the nanocomposites f(a-SiO2)/BST decreases first (f = 0.55 vol. %) and then increases rapidly with further increasing a-SiO2 content, which is proved to be caused mainly by changes of carrier concentration. In contrast, Seebeck coefficient S for the nanocomposites increases monotonically with increase in f, specially at T < similar to 380 K, suggesting that at low a-SiO2 (f = 0.55 vol. %) content, at least, the increase in S of the nanocomposite could be ascribed to energy filtering effect arising from enhanced carrier scattering by the interface potentials due to the embedded a-SiO2 nanoparticles. Owing to both increased power factor (S-2/rho) and reduced thermal conductivity caused by phonon scattering of nanoparticles as well as phase boundaries, the dimensionless figure of merit ZT of f(a-SiO2)/BST composite sample with f = 0.55 vol. % enhanced substantially at T < 390 K; specifically, ZT of the composite sample reaches 1.12 and 1.27 at similar to 303 K and similar to 363 K, respectively, which is, respectively, similar to 27% and similar to 20% larger than that (0.88 and 1.06) of BST, demonstrating that thermoelectric performance of BST can be effectively elevated by incorporation of a-SiO2 nanoparticles. (C) 2013 AIP Publishing LLC.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据