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arXiv · 1204.5260

Viable thermionic emission from graphene-covered metals

Elena Starodub·Norman C. Bartelt·Kevin F. McCarty
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Abstract

Thermionic emission from monolayer graphene grown on representative transition metals, Ir and Ru, is characterized by low-energy electron microscopy (LEEM). Work functions were determined from the temperature dependence of the emission current and from the electron energy spectrum of emitted electrons. The high-temperature work function of the strongly interacting system graphene/Ru(0001) is sufficiently low, 3.3 \pm 0.1 eV, to have technological potential for large-area emitters that are spatially uniform, efficient, and chemically inert. The thermionic work functions of the less strongly interacting system graphene/Ir(111) are over 1 eV larger and vary substantially (0.4 eV) between graphene orientations rotated by 30°.

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Elena Starodub, Norman C. Bartelt, Kevin F. McCarty. 2012-04-24. Viable thermionic emission from graphene-covered metals. https://doi.org/10.1063/1.4711212

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