Nanoscale dielectric capacitors composed of graphene and boron nitride layers: a first-principles study of high capacitance at nanoscale
Author
Özçelik, V. O.
Çıracı, Salim
Date
2013Source Title
Journal of Physical Chemistry C
Print ISSN
1932-7447
Publisher
American Chemical Society
Volume
117
Issue
29
Pages
15327 - 15334
Language
English
Type
ArticleItem Usage Stats
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Abstract
We investigate a nanoscale dielectric capacitor model consisting of two-dimensional, hexagonal h-BN layers placed between two commensurate and metallic graphene layers using self-consistent field density functional theory. The separation of equal amounts of electric charge of different sign in different graphene layers is achieved by applying an electric field perpendicular to the layers. The stored charge, energy, and the electric potential difference generated between the metallic layers are calculated from the first principles for the relaxed structures. Predicted high-capacitance values exhibit the characteristics of supercapacitors. The capacitive behavior of the present nanoscale model is compared with that of the classical Helmholtz model, which reveals crucial quantum size effects at small separations, which in turn recede as the separation between metallic planes increases. © 2013 American Chemical Society.