Modifications of Richardson-Dushman Thermionic Emission Current Density Equation for Nano- Materials

De, Dilip Kumar and Olawole, C. Olukunle (2016) Modifications of Richardson-Dushman Thermionic Emission Current Density Equation for Nano- Materials. In: 3rd International Conference On African Development Issues (CU-ICADI), May 9- May 11 2016, Covenant University, Ota, Nigeria.

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Abstract

The noble prize winning Richardson-Dushman equation (RDE) had been found to be quite applicable for thermionic emission from metals as far as temperature variation is concerned except the fact that the thermionic emission constant vary from metal to metal contrary to the original equation. We have derived expression for the temperature (T) dependence of work function (W) of a material considering thermal expansion and variation of the chemical potential with temperature. We find that the calculated dW/dT as well as the effective thermionic emission constant, Aeff of metals are fairly in good agreement with experimental results of many metals. We then modify the RDE by using temperature dependent work function and report the excellent fitting of thermionic emission current density data from monolayer graphene with our modified equation. We discuss briefly the potential application of the modified Richardson Dushman equation for thermionic emission from nano-materials. The latter will appear in details in paper II.

Item Type:	Conference or Workshop Item (Paper)
Uncontrolled Keywords:	Work function, temperature dependent chemical potential, modification of Richardson Dushman equation, thermionic emission, thermal expansion coefficient, nanomaterials, metals
Subjects:	Q Science > QC Physics
Divisions:	Faculty of Engineering, Science and Mathematics > School of Physics
Depositing User:	Mrs Hannah Akinwumi
Date Deposited:	27 Jun 2016 12:50
Last Modified:	27 Jun 2016 12:50
URI:	http://eprints.covenantuniversity.edu.ng/id/eprint/6632

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