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Materials-Metals 2017
Page 21
November 16-17, 2017 Paris, France
13th Annual Conference on
Materials Science, Metal and Manufacturing
Journal of Materials Science and Nanotechnology
Volume 1 Issue 2
J H Los et al., Mater Sci Nanotechnol 2017, 1:2
Extreme and unusual mechanical properties of
graphene
J H Los, A Fasolino and M I Katsnelson
Radboud University, Netherlands
Graphene and other 2D materials continue to surprise
scientists because of their unusual, special properties.
Not in the last place these also include their thermodynamic
and mechanical properties. Graphene is extremely stable
and strong, in contrast to the earlier belief expressed by the
Mermin-Wagner theorem that a 2D crystal would be unstable
against long wavelength fluctuations and crumple. Using an
approach based on nucleation theory and simulation, we have
been able to establish that graphene's melting temperature is
even higher (by a few hundred degrees) than that of graphite.
Concerning its mechanical properties, it turns out that the
elastic moduli of graphene are not material constants but,
at finite temperature, depend on the system size as a power
law, a peculiar behavior completely different from the kind
of change in the moduli observed when going from bulk
materials to clusters of nanoscale. To give an impression, for
a system of 1 cm2, the in-plane elastic constants are about
100 times (!) smaller while the out-of-plane elastic constant,
i.e. the bending rigidity, is about 10000 times (!!) larger than
for a system of nanometer size. This special size dependence,
predicted earlier in the theory ofmembranes and confirmed by
simulations and experiments has important implications for
nano-indentation of a graphene drum, used in experiments to
determine the Young modulus. Consequently, the Schwerin
equation, routinely used to derive the Young modulus from
such experiments, must be essentially modified for graphene
at room temperature and for micron sized samples, as we have
shown recently.
Recent Publications
• NDMermin (1968) Crystalline order in two dimensions.
Phys. Rev. 176(1):250-254.
• J H Los, K V Zakharchenko, M I Katsnelson and Annalisa
Fasolino (2015) Melting temperature of graphene. Phys.
Rev. B. 91:045415.
• David Robert Nelson (2004) Statistical Mechanics of
Membranes and Surfaces. World Scientific. Volume. Page
Numbers.
• M. I. Katsnelson (2012) Graphene: Carbon in two
dimensions. New York Cambridge University Press.
ISBN: 9780521195409.
• J H Los, M I Katsnelson, V Yazyev, K V Zakharchenko
and A Fasolino (2009) Scaling properties of flexible
membranes from atomistic simulations: Application to
graphene. Phys. Rev. B 80(12):121405(R).
Biography
Jan H Los completed PhD in the theory of condensed matter group at
the Radboud University in Nijmegen (Netherlands). He has worked as a
Researcher in different locations in Europe on various topics in the field of
theory of condensed matter, modelling and simulation. His current research
activities concentrate on graphene/2D systems, their (statistical-)mechanical
properties, development of effective interatomic interaction models enabling
large scale simulation.