• 文献标题:   Transport, magnetic and vibrational properties of chemically exfoliated few-layer graphene
  • 文献类型:   Article
  • 作  者:   MARKUS BG, SIMON F, CHACONTORRES JC, REICH S, SZIRMAI P, NAFRADI B, FORRO L, PICHLER T, VECERA P, HAUKE F, HIRSCH A
  • 作者关键词:   chemical exfoliation, esr, graphene, microwave conductivity, raman
  • 出版物名称:   PHYSICA STATUS SOLIDI BBASIC SOLID STATE PHYSICS
  • ISSN:   0370-1972 EI 1521-3951
  • 通讯作者地址:   Budapest Univ Technol Econ
  • 被引频次:   1
  • DOI:   10.1002/pssb.201552296
  • 出版年:   2015

▎ 摘  要

We study the vibrational, magnetic and transport properties of Few Layer Graphene (FLG) using Raman and electron spin resonance spectroscopy and microwave conductivity measurements. FLG samples were produced using wet chemical exfoliation with different post-processing, namely ultrasound treatment, shear mixing, and magnetic stirring. Raman spectroscopy shows a low intensity D mode which attests a high sample quality. The G mode is present at 1580 cm(-1) as expected for graphene. The 2D mode consists of 2 components with varying intensities among the different samples. This is assigned to the presence of single and few layer graphene in the samples. Electron Spin Resonance (ESR) spectroscopy shows a main line in all types of materials with a width of about 1 mT and a g-factor in the range of 2.005-2.010. Paramagnetic defect centers with a uniaxial g-factor anisotropy are identified, which shows that these are related to the local sp2 bonds of the material. All kinds of investigated FLGs have a temperature dependent resistance which is compatible with a small gap semiconductor. The difference in resistance is related to the different grain size of the samples. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim