Graphene exhibits strange ‘melting’ behavior

Physicists from the Moscow Institute of Physics and Technology and the Institute for High Pressure Physics of the Russian Academy of Sciences have set out to refine the melting curve of graphite using computer modeling, and made interesting observations on graphene's melting properties.

The team'a results show that the liquid carbon structure undergoes changes above the melting curve of graphene. The researchers explain that no graphene melting experiments have been conducted. Previously, computer models predicted the melting point of graphene at 4,500 or 4,900 K. Two-dimensional carbon was therefore considered to have the highest melting point in the world.

In our study, we observed a strange ‘melting’ behavior of graphene, which formed linear chains. We showed that what happens is it transitions from a solid directly into a gaseous state. This process is called sublimation, commented Associate Professor Yuri Fomin of the Department of General Physics, MIPT. The findings enable a better understanding of phase transitions in low-dimensional materials, which are considered an important component of many technologies currently in development, in fields from electronics to medicine.

The team's calculations show that the melting temperature of graphene in an argon atmosphere is close to the melting temperature of graphite.