Temperature dependence of the Raman spectra of multilayer graphene nanoribbons fabricated by unzipping method
Graphical abstract
Introduction
Graphene, a two-dimensional honeycomb lattice of carbon atoms, has remarkable electric, mechanical, thermal, and optical properties [1]. In particular, the carrier mobility of graphene is predicted theoretically more than 250,000 cm2 V−1 s−1 at room temperature, therefore, graphene is expected to be applied as a next-generation electronic device. However, applications in semiconductor technologies such as a transistor are restricted because graphene has a zero-band gap [2]. Graphene nanoribbons (GNRs), defined quasi-one-dimensional graphene with nanometer-width, have been attracted great attention as one of attempt to open a band gap in graphene [3]. Numerous studies about their fabrications and properties have been reported, but especially their basic thermal properties are still not clear due to few experimental studies. The understanding of the thermal properties of GNRs is important for their device applications such as field effect transistors [4] and sensors [5], since the devices composed of heterogeneous composites with the interfaces are fabricated and operated in various temperature environment.
Generally, Raman spectroscopy is an indispensable method to obtain important information such as structural and electronic properties of carbon materials [6]. For the evaluation of thermal property, the temperature dependence of Raman spectra has been reported for graphite [[7], [8], [9]], graphene [[10], [11], [12], [13], [14], [15]], carbon nanotubes [[16], [17], [18], [19], [20], [21]]. The comparison and discussion of the temperature dependence are needed for practical applications. However, the temperature dependence of GNRs has not been reported yet to the best of our knowledge.
In this study, we measured the temperature dependence of the Raman spectra of multilayer GNRs (MLGNRs) fabricated by unzipping method [22] which is one of the most industrial synthesis method [23,24] to understand the thermal characteristics of MLGNRs. Especially, we aimed to observe a completely isolated GNR without bundles and segregations to understand the intrinsic thermal property of MLGNRs. As a result, we succeeded in observing the intrinsic temperature dependence of a MLGNR for the first time. The temperature-dependent behavior with non-linear quadratic curve will be explained by the theoretical model including anharmonic phonon interaction with 3- and 4-phonon processes, and compared with typical nanocarbon materials has been reported so far.
Section snippets
Materials and methods
MLGNRs fabricated by a method of unzipping MWCNTs were purchased from SIGMA-ALDRICH (Prod. No. 797774) [25]. 10 mg of MLGNRs were dispersed in 10 ml of ethanol with a homogenizer (Dr. HIELSCHER UP400S) and dropped onto SiO2 (285 nm)/Si substrate. In order to avoid aggregations of MLGNRs, the SiO2/Si substrate was placed on a hot plate heated to about 80 °C before dropping. The prepared sample was observed by using an optical microscope (OLYMPUS BX51) and a field emission scanning electron
Results and discussion
Fig. 1(a) shows the typical SEM image of a MLGNR dispersed on SiO2/Si substrate at 300 K. A magnified figure of the square area in (a) is shown in Fig. 1(b). Note that such isolated samples were selected in Raman measurements. It is found that the length and width of the MLGNR are about 5–10 μm and 200 nm respectively. These features are in good agreement with those in one of typical of GNRs reported so far [22]. However, it was hard to successfully measure the thickness of MLGNRs by using an
Conclusion
We have succeeded in observing the intrinsic temperature dependence of a completely isolated MLGNR with a width of ~200 nm. The downshift of the G band frequency is clearly observed with increasing temperature. The change in the G band is reversible in the thermal cycles between 300 K and 700 K. This reversible behavior reflects intrinsic thermal properties without damages. The temperature-dependent behavior with non-linear quadratic curve is explained by theoretical model with anharmonic
Author's contributions
All authors contributed equally to this work.
Author statement
Marina Tsujimoto: Conceptualization, Methodology, Writing-Original Draft. Makoto Tanimura: Formal analysis, Investigation, Resources. Masaru Tachibana: Supervision.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgements
This study was in part supported by Iketani Science and Technology Foundation (0291078-A) and JSPS KAKENHI (17K06797) in Japan.
References (41)
- et al.
Chemically derived, ultrasmooth graphene nanoribbon semiconductors
Science
(2008) - et al.
Experimental study of graphitic nanoribbon films for ammonia sensing
J. Appl. Phys.
(2011) - et al.
The intrinsic temperature-dependent Raman spectra of graphite in the temperature range from 4K to 1000K
Carbon
(2019) - et al.
Temperature-dependent Raman investigation on suspended graphene: contribution from thermal expansion coefficient mismatch between graphene and substrate
Carbon
(2016) - et al.
Temperature dependent Raman investigation of multiwall carbon nanotubes
J. Appl. Phys.
(2018) - et al.
Unzipping of multi-wall carbon nanotubes with different diameter distributions: effect on few-layer graphene oxide obtention
Appl. Surf. Sci.
(2017) - et al.
Intercalation-assisted longitudinal unzipping of carbon nanotubes for green and scalable synthesis of graphene nanoribbons
Sci. Rep.
(2016) - et al.
Graphite thermal expansion relationship for different temperature ranges
Carbon
(2005) - et al.
Anharmonicity of graphite from UV Raman spectroscopy to 2700 K
Carbon
(2013) - et al.
Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems
Nanoscale
(2015)
Graphene transistors
Nat. Nanotechnol.
Rational fabrication of graphene nanoribbons using a nanowire etch mask
Nano Lett.
Raman spectroscopy as a versatile tool for studying the properties of graphene
Nat. Nanotechnol.
Temperature-dependent Raman spectra and anomalous Raman phenomenon of highly oriented pyrolytic graphite
Phys. Rev. B
The intrinsic temperature effect of the Raman spectra of graphite
Appl. Phys. Lett.
Temperature dependence of the Raman spectra of graphene and graphene multilayers
Nano Lett.
Environment-induced effects on the temperature dependence of Raman spectra of single-layer graphene
J. Phys. Chem. C
Negative thermal expansion coefficient of graphene measured by Raman spectroscopy
Nano Lett.
Temperature dependence of the Raman spectra of polycrystalline graphene grown by chemical vapor deposition
Appl. Phys. Lett.
Study of the substrate-induced strain of as-grown graphene on Cu (100) using temperature-dependent Raman spectroscopy: estimating the mode Grüneisen parameter with temperature
J. Phys. Chem. C
Cited by (13)
Influence of temperature and nonlinear damping on mechanical properties of single-walled carbon nanotubes
2024, Diamond and Related MaterialsThe effect of Co-encapsulated GNPs-CNTs nanofillers on mechanical properties, degradation and antibacterial behavior of Mg-based composite
2023, Journal of the Mechanical Behavior of Biomedical MaterialsPhonon anharmonicities in 7-armchair graphene nanoribbons
2022, CarbonCitation Excerpt :However, limited by the purity CNTs usually exhibit multicomponents in RBM [26], hindering the accurate investigations on the temperature dependency. The G mode of ∼200-nm-wide multilayer GNRs (MLGNRs) via unzipping multi-walled CNT shows a linear downshift in frequency with temperature in the range from 400 to 700 K [27]. In contrast, in temperature range lower than 400 K, it shows a nonlinear downshift in frequency with temperature, attributed to the quartic-phonon decay processes rather than cubic-phonon ones.
Substrate effect on phonon in graphene layers
2023, Carbon LettersAnti-Stokes Raman Scattering of the Smallest Carbon Nanowires Made of Long Linear Carbon Chains Inserted inside Single-Walled Carbon Nanotubes
2023, Journal of Physical Chemistry C