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Preparation and Evaluation of Hybrid Composites of Chemical Fuel and Multi-walled Carbon Nanotubes in the Study of Thermopower Waves
Published on: April 10, 2015
Thermopower enhancement in nanowires via junction effects
Nicolas B Duarte1, Gerald D Mahan, Srinivas Tadigadapa
1Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Nano Letters
|January 27, 2009
Summary
Researchers observed a significant peak in thermopower near room temperature for "junctioned" gold nanowires. This thermoelectric enhancement, attributed to electron tunneling and Coulombic effects, led to a hundredfold increase in ZT, a key figure of merit.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Thermopower is a crucial property for thermoelectric materials.
- Nanowires offer unique electronic properties due to quantum confinement.
- Understanding thermoelectricity in nanostructures is vital for energy harvesting applications.
Purpose of the Study:
- To investigate the thermopower of gold nanowires, both straight and "junctioned".
- To explore the thermoelectric properties of "junctioned" gold nanowires near room temperature.
- To elucidate the underlying physical mechanisms responsible for observed thermoelectric enhancements.
Main Methods:
- Utilized a micromachined thermoelectric workbench for precise measurements.
- Performed thermopower measurements on free-standing, straight, and "junctioned" gold nanowires.
- Analyzed data considering electron tunneling and Coulombic effects across junctions.
Main Results:
- Straight gold nanowires exhibited bulk-like thermopower.
- A novel peak in thermopower was observed near room temperature for "junctioned" gold nanowires.
- A hundredfold enhancement in the thermoelectric figure of merit (ZT) was recorded for "junctioned" nanowires.
Conclusions:
- "Junctioned" gold nanowires demonstrate significantly enhanced thermoelectric properties.
- The observed thermopower peak is explained by a model involving electron tunneling and Coulombic effects.
- These findings highlight the potential of engineered nanowire junctions for advanced thermoelectric devices.
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