Bi2Sr2-xNaxCo2Ox ve Bi2Sr2-xKxCo2Ox thermoelectric materials production with LFZ technique and characterization

In this study, Bi2Sr2-xNaxCo2Ox and Bi2Sr2-xKxCo2Ox (where x = 0.0, 0.025, 0.050, 0.075, 0.10, 0.125 and 0.15) thermoelectric materials were synthesized in a controlled and homogeneous manner by the conventional solid-state method. By pressing the powdered materials (bulk structure), thermoelectric properties such as Seebeck coefficient, electrical and thermal conductivity, Power factor and Figure of Merit, moreover XRD and SEM structural analyzes and magnetic measurements were performed in this thesis work. Then, the obtained powders were turned into rods by means of iso-static press and the grain orientation was realized by Laser Floating Zone (LFZ) technique. The obtained cylindrical rods were applied to an extra heat treatment. Finally, the thermoelectric, structural and magnetic properties of extra heat untreated rods (as-grown structure) and sintered rods (fiber structure) were measured and compared with each other.