National Changhua University of Education Institutional Repository : Item 987654321/14261

English | 正體中文 | 简体中文 | Items with full text/Total items : 6507/11669
Visitors : 29943960 Online Users : 483

RC Version 3.2 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.

Scope Adv. Search

Login ‧ Upload ‧ Help ‧ About ‧ Administer

NCUEIR > College of Science > Department of Physics > Periodical Articles > Item 987654321/14261

Please use this identifier to cite or link to this item: http://ir.ncue.edu.tw/ir/handle/987654321/14261

Title:	High-temperature Thermoelectric Properties of Late Rare Earth-doped Ca3Co4O9+δ
Authors:	Nong, N. V.;Liu, Chia-Jyi;Ohtaki, M.
Contributors:	物理學系
Keywords:	Thermoelectric materials;Oxide materials;Solid state reactions;Thermoelectrics
Date:	2011-01
Issue Date:	2012-09-10T06:16:37Z
Publisher:	Elsevier
Abstract:	Misfit-layered oxides Ca3−xLnxCo4O9+δ with Ln = Dy, Er, Ho, and Lu were synthesized using solid state reactions. The resulting samples were hot-pressed (HP) at 1123 K in air for 2 h under a uniaxial pressure of 60 MPa. Thermoelectric properties of Ca3−xLnxCo4O9+δ were investigated up to 1200 K. Both the Seebeck coefficient and electrical resistivity increase upon Ln substitution for Ca. Among the Ln-doped samples, the magnitude of Seebeck coefficient tends to increase with decreasing ionic radius of Ln3+. The Ln-doped samples exhibit a lower thermal conductivity than the non-doped one due to a decrease of their lattice thermal conductivity. The dimensionless figure of merit, ZT, reaches 0.36 at 1073 K for the Ca2.8Lu0.2Co4O9+δ sample, which is about 1.6 times larger than that for the non-doped counterpart.
Relation:	Journal of Alloys and Compounds, 509(3): 977-981
Appears in Collections:	[Department of Physics] Periodical Articles

Files in This Item:

File	Size	Format
index.html	0Kb	HTML	690	View/Open