Biomedical Engineering Reference
In-Depth Information
The prospects for a further research we are interested in are
really more on the academic side, in pursuit of new physics regarding
the hydrogen-graphene system and related materials firstly by more
accurate treatment of weak, noncovalent chemical interactions. Till
date, the existing implementations of DFT are still lacking in topics
such as van der Waals interactions.
In this light, future theoretical work may be focused more on
taking into account possible physisorption states, which may have
been neglected so far, and hydrogen bonding in condensed matter
systems, by working on post-GGA methods accounting for nonlocal
correlation energy. Furthermore, beyond electronic structure
calculations, a relatively untouched topic in which we are also
interested is the quantum behavior of “hot” hydrogen atom motion
“on,” “along,” and perhaps even “through” the graphene sheet, as well
as within the intercalation region of bilayer graphene. The small
mass of hydrogen and the relatively less important role of substrate
reconstruction for rapidly diffusing adatoms suggest that a departure
from a purely classical treatment of proton motion is necessary. This
may be very important for other small adatoms, as pointed out in a
recent study on Li motion on graphene [40].
Acknowledgments
We are very grateful to the Toyota Motor Corporation, the Japan
Society for the Promotion of Science (JSPS) and the Ministry
of Education, Culture, Sports, Science and Technology of Japan
(MEXT) through their Special Coordination Funds for the Global
Center of Excellence (GCOE) program (H08) “Center of Excellence
for Atomically Controlled Fabrication Technology.” Some of
the calculations have been performed by computer facilities of
the Cybermedia Center (Osaka University), the Institute of Solid
State Physics (ISSP) Super Computer Center (University of Tokyo),
the Yukawa Institute (Kyoto University), and the Japan Atomic
Energy Agency (JAEA).
References
1. Chan, K. T., Neaton, J. B., and Cohen, M. L. (2008). First-principles study
of metal adatom adsorption on graphene,
, 235430.
2. Higai, S., Honda, A., Nishida, K., Wada, N., and Sakabe, Y. (2008). Alkali-
metal lithium on graphite monolayer surface: Theoretical study,
J. Phys. Chem. Solids
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