Graduation Year
2021
Document Type
Thesis
Degree
M.S.
Degree Name
Master of Science (M.S.)
Degree Granting Department
Physics
Major Professor
George S. Nolas, Ph.D.
Committee Member
Jacob Gayles, Ph.D.
Committee Member
Dmitri Voronine, Ph.D.
Keywords
anisotropic transport, chalcogenides, layered materials, XRD rocking curve
Abstract
Thermoelectric devices provide the means for direct conversion between heat and electricity. The device conversion efficiency, or performance, is directly related to the thermoelectric figure of merit, ZT, of the working materials. Bismuth telluride alloys are the materials currently in use in most thermoelectric devices for near room temperature solid-state refrigeration and power conversion applications. The vast majority of publications in the literature on thermoelectricity report on investigations towards developing new materials with enhanced thermoelectric properties, however Bi2Te3 alloys have been used in thermoelectric devices for decades.
In this thesis, an investigation of crystallographic texturing on large grain polycrystalline n and p-type Bi2Te3 alloys, and the effect of texturing on the transport properties, is discussed. Bi2Te3 is a layered material, and since the arrangement of atoms in the structure leads to strong anisotropy the role of texturing continues to be of primary importance for optimum device performance using these materials. Texturing both parallel and perpendicular to the growth direction of polycrystalline n and p-type Bi2Te3 alloys synthesized from the melt will be described. The texture-thermoelectric property relationships are described in detail. These materials are highly textured with superior thermoelectric properties compared to similar polycrystalline materials with randomly oriented grains.
Scholar Commons Citation
Ojo, Oluwagbemiga P., "Texturing in Bi2Te3 Alloy Thermoelectric Materials: An Applied Physics Investigation" (2021). USF Tampa Graduate Theses and Dissertations.
https://digitalcommons.usf.edu/etd/9204
