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arXiv · 0906.0500

On the electric conductivity of highly ordered monolayers of monodisperse metal nanoparticles

Denis Greshnykh·Andreas Fromsdorf·Horst Weller·Christian Klinke
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Abstract

Monolayers of colloidally synthesized cobalt-platinum nanoparticles of different diameters characterized by TEM (transmission electron microscopy) were deposited on structured silicon oxide substrates and characterized by SEM (scanning electron microscopy), GISAXS (grazing incidence x-ray scattering), and electric transport measurements. The highly ordered nanoparticle films show a thermally activated electron hopping between spatially adjacent particles at room temperature and Coulomb blockade at low temperatures. We present a novel approach to experimentally determine the particles charging energies giving values of 6.7-25.4 meV dependent on the particles size and independent of the interparticle distance. These observations are supported by FEM (finite element method) calculations showing the self-capacitance to be the determining value which only depends on the permittivity constant of the surrounding space and the particles radius.

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Denis Greshnykh, Andreas Fromsdorf, Horst Weller, Christian Klinke. 2009-06-02. On the electric conductivity of highly ordered monolayers of monodisperse metal nanoparticles. https://doi.org/10.1021/nl803520r

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