• 文献标题:   The split-up of G band and 2D band in temperature-dependent Raman spectra of suspended graphene
  • 文献类型:   Article
  • 作  者:   LIU Y, SHI YF, ZHOU WG, SHI W, DANG W, LI XL, LIANG BL
  • 作者关键词:   graphene, raman spectroscopy, strain, the splitup of g band 2d band
  • 出版物名称:   OPTICS LASER TECHNOLOGY
  • ISSN:   0030-3992 EI 1879-2545
  • 通讯作者地址:  
  • 被引频次:   8
  • DOI:   10.1016/j.optlastec.2021.106960 EA FEB 2021
  • 出版年:   2021

▎ 摘  要

Dedicated Raman spectroscopy investigations in the temperature range from 78 K to 298 K were performed for the graphene suspended above round holes on SiO2/Si substrate (the suspended graphene, SUG), in comparison with the surrounding graphene adhered to solid SiO2/Si substrate (the substrate supported graphene, SSG). The results confirmed that one-layer SUG (1L-SUG) was subjected to strains originated from the surrounding 1L-SSG due to the different area and shape around the hole along different directions. In further, the split-up of G band and 2D band were observed at low temperature because of the enhanced anisotropic strains in 1L-SUG due to the mismatch of thermal expansion coefficient (TEC) between the 1L-SSG and SiO2/Si substrates. The temperature dependent (T-dependent) frequency shifts for the G band and 2D band in 1L-SUG and 1L-SSG were consistent with previous Raman investigations. Therefore, the micro-hole boundary effect in suspended graphene play a significant role in determination of the properties for graphene materials and graphene-based flexible devices.