0

Full Content is available to subscribers

Subscribe/Learn More  >

Photo- and Thermionic Emission From Potassium-Intercalated Single-Walled Carbon Nanotube Arrays

[+] Author Affiliations
Tyler L. Westover, Aaron D. Franklin, Timothy S. Fisher, Ronald G. Reifenberger

Purdue University, West Lafayette, IN

Paper No. ENIC2008-53034, pp. 1-10; 10 pages
doi:10.1115/ENIC2008-53034
From:
  • ASME 2008 3rd Energy Nanotechnology International Conference collocated with the Heat Transfer, Fluids Engineering, and Energy Sustainability Conferences
  • ASME 2008 3rd Energy Nanotechnology International Conference
  • Jacksonville, Florida, USA, August 10–14, 2008
  • Conference Sponsors: Nanotechnology Institute
  • ISBN: 0-7918-4323-9 | eISBN: 0-7918-3832-3
  • Copyright © 2008 by ASME

abstract

Vacuum thermionic electron emission has been considered for many years as a means to convert heat or solar energy directly into electrical power. However, an emitter material has not yet been identified that has a sufficiently low work function and that is stable at the elevated temperatures required for thermionic emission. Recent theoretical models predict that photonic and thermal excitation can combine to significantly increase overall efficiency and power generation capacity beyond that which is possible with thermionic emission alone. Carbon nanotubes (CNTs) intercalated with potassium have demonstrated work functions as low as 2.0 eV, and low electron scattering rates observed in small diameter CNTs offer the possibility of efficient photoemission. This study uses a Nd:YAG laser to irradiate potassium-intercalated single-walled CNTs (K/SWCNTs), and the resultant energy distributions of photo- and thermionic emitted electrons are measured using a hemispherical electron energy analyzer for a wide range of temperatures. We observe that the work function of K/SWCNTs is temperature dependent and has a minimum of approximately 2.0 eV at approximately 600 K. At temperatures above 600 K, the measured work function K/SWCNTs increases with temperature, presumably due to deintercalation of potassium atoms.

Copyright © 2008 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In