Characterization and Control of the Barrier for Hydrogen Adsorption on Graphene
ORAL
Abstract
We study the chemisorption of atomic hydrogen on graphene. The barrier for chemisorption is about 0.21 eV. We explain the evolution of the partial density of states of the hydrogen and carbon atoms in graphene upon adsorption with a simple three-site Hubbard model. The barrier results from the competition between the pi-bonding between carbon atoms and the covalent bonding with hydrogen. With knowledge of the principles at play, we propose adjustments to the graphene plane which lower or eliminate this adsorption barrier. With a reduced barrier, formation of graphane can be facilitated, and applications for selective hydrogen desorption to create channels are discussed.
*This work is supported by the Donors of the American Chemical Society Petroleum Research Fund as well as by the US-Israel Binational Science Foundation grant 2006238 in collaboration with Prof. Ezra Bar-Ziv at the Ben-Gurion University of the Negev.
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