Temperature Dependence of Raman-Active In-Plane E2g Phonons in Layered Graphene and h-BN Flakes

• Main Authors: Xiaoli Li, Jian Liu, Kai Ding, Xiaohui Zhao, Shuai Li, Wenguang Zhou, Baolai Liang
• Format: Article
• Language: English
• Published: SpringerOpen 2018-01-01
• Series: Nanoscale Research Letters
• Subjects: Graphenes; h-BNs; In-plane E2g phonon; Temperature dependence
• Online Access: http://link.springer.com/article/10.1186/s11671-018-2444-2
• ISSN: 1931-7573; 1556-276X

Abstract Thermal properties of sp2 systems such as graphene and hexagonal boron nitride (h-BN) have attracted significant attention because of both systems being excellent thermal conductors. This research reports micro-Raman measurements on the in-plane E2g optical phonon peaks (~ 1580 cm−1 in graphene layers and ~ 1362 cm−1 in h-BN layers) as a function of temperature from − 194 to 200 °C. The h-BN flakes show higher sensitivity to temperature-dependent frequency shifts and broadenings than graphene flakes. Moreover, the thermal effect in the c direction on phonon frequency in h-BN layers is more sensitive than that in graphene layers but on phonon broadening in h-BN layers is similar as that in graphene layers. These results are very useful to understand the thermal properties and related physical mechanisms in h-BN and graphene flakes for applications of thermal devices.