Synthesis and Carriers Transport Characterization of Iron-based Superconducting Material FeSe

• Main Authors: Hsueh-Jung Huang, 黃雪蓉
• Other Authors: C. J. Liu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/12223965793020181030

碩士 === 國立彰化師範大學 === 光電科技研究所 === 99 === The recent discovery of some Fe-based materials, particularly LaAsFeO have garnered much attention lately as unconventional high-Tc superconductors. But the quaternary material has complex structure; we transferred to research binary iron-based material. More recently, β-FeSe, has been identified as a superconductor with Tc=8 K. In addition to studying the energy conversion behavior of thermoelectric materials, many research groups are engaged in the search for alternative energy sources and also for materials, such as superconductors, which are considered important for usage in energy conservation applications. The parent β-FeSe crystallizes at room temperature with the tetragonal PbO-type structure (space groupof P4/nmm, Fe at 2a site, Se at 2c site) and is made up by stacking of edge-sharing FeSe4 tetrahedra layers. In this paper, we prepared the iron-based material by solid state sintering, and tried to improve the thermoelectric properties by doping bismuth and manganese. Our results point to the thermopower data suggest negative charge carriers along with a large enhancement of the Seebeck coefficient, S −80 μV/K near T=100 K.