2026-05-22T08:42:48Zhttps://keep.lib.asu.edu/oai/requestoai:keep.lib.asu.edu:node-1532442024-12-20T18:25:12Zoai_pmh:alloai_pmh:repo_items153244
https://hdl.handle.net/2286/R.I.27485
http://rightsstatements.org/vocab/InC/1.0/
All Rights Reserved
2014
x, 37,15 p. : ill. (some col.)
Masters Thesis
Academic theses
Text
eng
Jaber, Abbas
Wang, Robert
Wang, Liping
Rykaczewski, Konrad
Arizona State University
Partial requirement for: M.S., Arizona State University, 2014
Includes bibliographical references (p. 35-36)
Field of study: Mechanical engineering
Nanostructured materials show signicant enhancement in the thermoelectric g-<br/><br/>ure of merit (zT) due to quantum connement eects. Improving the eciency of<br/><br/>thermoelectric devices allows for the development of better, more economical waste<br/><br/>heat recovery systems. Such systems may be used as bottoming or co-generation<br/><br/>cycles in conjunction with conventional power cycles to recover some of the wasted<br/><br/>heat. Thermal conductivity measurement systems are an important part of the char-<br/><br/>acterization processes of thermoelectric materials. These systems must possess the<br/><br/>capability of accurately measuring the thermal conductivity of both bulk and thin-lm<br/><br/>samples at dierent ambient temperatures.<br/><br/>This paper discusses the construction, validation, and improvement of a thermal<br/><br/>conductivity measurement platform based on the 3-Omega technique. Room temperature<br/><br/>measurements of thermal conductivity done on control samples with known properties<br/><br/>such as undoped bulk silicon (Si), bulk gallium arsenide (GaAs), and silicon dioxide<br/><br/>(SiO2) thin lms yielded 150 W=m􀀀K, 50 W=m􀀀K, and 1:46 W=m􀀀K respectively.<br/><br/>These quantities were all within 8% of literature values. In addition, the thermal<br/><br/>conductivity of bulk SiO2 was measured as a function of temperature in a Helium-<br/><br/>4 cryostat from 75K to 250K. The results showed good agreement with literature<br/><br/>values that all fell within the error range of each measurement. The uncertainty in<br/><br/>the measurements ranged from 19% at 75K to 30% at 250K. Finally, the system<br/><br/>was used to measure the room temperature thermal conductivity of a nanocomposite<br/><br/>composed of cadmium selenide, CdSe, nanocrystals in an indium selenide, In2Se3,<br/><br/>matrix as a function of the concentration of In2Se3. The observed trend was in<br/><br/>qualitative agreement with the expected behavior.<br/><br/>i
Mechanical Engineering
Thermal conductivity
Nanostructured materials
Construction of a thermal conductivity measurement platform for bulk and thin film materials based on the 3-Omega technique