A Novel Electrode Material for Thermionic Power Generation, Phase I

Metadata Updated: May 2, 2019

The conversion of heat to power has proven to be vital in flight missions where solar power generation is not an option. Radioisotope thermoelectric generators that converted heat produced by a decaying nuclear source to power have been used on missions such as Cassini, New Horizons, Galileo, Ulysses and the Mars Science Laboratory. Although never flown by the United States, thermionic converters have also been investigated for space applications. Their improved efficiency over thermoelectric generators makes them an attractive option, but the high operating temperatures required have thus far been a significant obstacle to their use.
Thermionic generators convert heat energy directly into electrical power. An emitter electrode on a heat source emits electrons across a vacuum gap to a cold electrode. The generated current is pumped through a load where it can do useful work before it is returned to the emitter. Thermionic generators do not use any moving parts or working fluid, which results in highly reliable devices that do not need frequent maintenance. Unlike thermoelectric generators, which have exhibited efficiencies only up to about 8%, state-of-the-art thermionic generators operate with efficiencies approaching 20%. This proposal seeks to study the use of the nanomaterial C12A7 electride as an electrode material. C12A7 electride has been shown to emit stably at temperatures in excess of 1600 degrees C and has a measured work function between 0.8-2.1 eV. Due to its low work function, C12A7 electride has the potential to greatly improve the efficiency of the state-of-the-art in thermionic energy conversion as well as enable device operation at much lower temperatures than is currently possible. Busek previously has investigated C12A7 electride in thermionic emission configurations for space propulsion hollow cathode applications. In the proposed work, Busek will evaluate the potential benefits of a C12A7 electride thermionic converter electrode.

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Public: This dataset is intended for public access and use. License: U.S. Government Work

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Metadata Created Date August 1, 2018
Metadata Updated Date May 2, 2019

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Harvested from NASA Data.json

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Resource Type Dataset
Metadata Created Date August 1, 2018
Metadata Updated Date May 2, 2019
Publisher Space Technology Mission Directorate
Unique Identifier TECHPORT_90130
Maintainer Email
Public Access Level public
Bureau Code 026:00
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Metadata Catalog ID https://data.nasa.gov/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
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Datagov Dedupe Retained 20190501230127
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Harvest Source Id 39e4ad2a-47ca-4507-8258-852babd0fd99
Harvest Source Title NASA Data.json
Data First Published 2016-12-01
Homepage URL https://techport.nasa.gov/view/90130
License http://www.usa.gov/publicdomain/label/1.0/
Data Last Modified 2018-07-19
Program Code 026:027
Source Datajson Identifier True
Source Hash 7300d505fa0c97a9cbe29964e32067f5cfbc49c9
Source Schema Version 1.1

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