TY - JOUR
T1 - Property-processing relations in developing thermoelectric ceramics
T2 - Na1-x Co2O4
AU - Yamakawa, Hiroo
AU - Lee, Soonil
AU - Takagi, Hiroshi
AU - Randall, Clive A.
N1 - Funding Information:
Acknowledgements This study is based upon work supported by the National Science Foundation, as part of the Center for Dielectric Studies under Grant No. 0628817. The authors wish to acknowledge the CDS membership and NSF I/UCRC program for support on this topic.
PY - 2011/4
Y1 - 2011/4
N2 - Polycrystalline Na1-x Co2O4 is a promising p-type oxide thermoelectric, and it was investigated in a property-processing study to enhance the thermoelectric properties for high temperature applications. The density of the ceramics was improved by a post-milling process, and consequently, we obtained better thermoelectric power factors (PF) due to an associated improvement in electrical conductivity. Through a milling process, and sintering at 1203 K, we obtained an enhanced thermoelectric power factor of ~4 μW/cm K2 at 500 K for randomly orientated polycrystalline ceramics. The Seebeck coefficient variation with temperature demonstrates through modeling that the conduction mechanism changed from metallic to a semiconducting behavior between temperatures 300 to 400 K.
AB - Polycrystalline Na1-x Co2O4 is a promising p-type oxide thermoelectric, and it was investigated in a property-processing study to enhance the thermoelectric properties for high temperature applications. The density of the ceramics was improved by a post-milling process, and consequently, we obtained better thermoelectric power factors (PF) due to an associated improvement in electrical conductivity. Through a milling process, and sintering at 1203 K, we obtained an enhanced thermoelectric power factor of ~4 μW/cm K2 at 500 K for randomly orientated polycrystalline ceramics. The Seebeck coefficient variation with temperature demonstrates through modeling that the conduction mechanism changed from metallic to a semiconducting behavior between temperatures 300 to 400 K.
UR - https://www.scopus.com/pages/publications/79751533649
UR - https://www.scopus.com/inward/citedby.url?scp=79751533649&partnerID=8YFLogxK
U2 - 10.1007/s10853-010-5039-6
DO - 10.1007/s10853-010-5039-6
M3 - Article
AN - SCOPUS:79751533649
SN - 0022-2461
VL - 46
SP - 2064
EP - 2070
JO - Journal of Materials Science
JF - Journal of Materials Science
IS - 7
ER -