An approach to produce single and double layer graphene from re-exfoliation of expanded graphite

Dhakate, Sanjay R.; Chauhan, Neha; Sharma, Sanjeev; Tawale, J.S.; Singh, Sukhvir; Sahare, P.D.; Mathur, R.B.

doi:10.1016/j.carbon.2010.12.068

Cited by 139 publications

(49 citation statements)

References 42 publications

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“…To affi rm the crystalline nature of the GO, a selected area electron diffraction (SAED) pattern was obtained for the GO (Figure 2 i, inset); it is quite similar to the typical six-fold symmetry obtained for graphite oxide, [ 24 ] suggesting that the obtained GO sheets were not completely amorphous. Importantly, it should be noticed from the SAED pattern that the inner hexagonal spots 1100 { } were more intense than the outer hexagonal spots 1120 { }, suggesting the presence of monolayer GO sheets rather than a multilayer; this agrees very well with previous reports, [ 25,26 ] and it is also consistent with our AFM results. The edge image of the monolayer GO at high magnifi cation is available in the SI ( Figure S3b).…”

Section: Resultssupporting

confidence: 94%

N₂‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO₂/Si Substrate Via the Langmuir–Blodgett Technique

Chauhan

Palaninathan

Raveendran

et al. 2015

Adv Materials Inter

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building block for the next generation of micro-and nanoscale electronic devices. Signifi cant progress has been made in the area from its synthesis to applications; [ 3 ] however, from the industrial point of view, a grand challenge still exists in its selective placement, self-assembly, and patterning, which would enable a variety of large-area electronics that could be applied in a variety of technologically advanced areas, including the fi elds of electronics, photonics, optoelectronic devices, biological and chemical sensing, and energy conversion. It is extremely desirable to develop a technique for the successful selective placement and patterning of graphene for a low-cost and high-throughput fabrication of large-area 2D patterned graphene and graphene oxide (GO), in which the dimensions are controllable. To date, extensive work has been devoted to the self-assembly and patterning of GO and graphene using various techniques, including electron beam lithography, photolithography, scanning probe lithography, block-copolymer lithography, soft transfer printing, masked laser patterning, direct laser patterning, a combination of wettability modulation and spin-coating, and ink-jet printing. [ 4 ] Complex patterned structures can be formed using the current lithography techniques; but during this process the residual polymers may contaminate the graphene surface and interfere with subsequent metallization steps. Apart from that, these processes are time-consuming and involve highly expensive and sophisticated equipment with low throughput; hence, there is an urgent need for a simple, time-saving and cost-effective method that can yield high throughput with greater reproducibility for the effi cient fabrication of 2D patterned graphene and various nanostructures over a large area.Additionally, another important issue, yet to be resolved, is how to achieve precise control over the alignment and positioning of graphene sheets from the stock solution on to the substrate; this is one of the vital steps in the processing of graphene-based devices, especially for the large-scale fabrication of parallel device arrays, [ 5 ] which are highly desirable for commercial applications.Precise control of the placement and patterning of graphene on various substrates has tremendous impact in many fi elds, such as nanoscale electronics, multifunctional optoelectronic devices, and molecular sensing. A one-step facile technique involving N 2 -plasma promotes surface modifi cation and enhances the surface wettability of the substrate. The technique is employed to create partially hydrophilic surfaces on SiO 2 /Si substrate with the aid of various templates, enabling the selective deposition, alignment, and formation of patterns comprising monolayer graphene oxide (GO) sheets; it successfully uses the Langmuir-Blodgett (LB) deposition technique over a large area without the need of any sophisticated equipment. Various characterization techniques are carried out in order to understand the possible mechanism behind the pinning of th...

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Section: Resultssupporting

confidence: 94%

N₂‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO₂/Si Substrate Via the Langmuir–Blodgett Technique

Chauhan

Palaninathan

Raveendran

et al. 2015

Adv Materials Inter

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“…Number of layers (thickness) TEM [21] AFM [21] Raman spectroscopy [21,22] Optical absorbance measurements [23] Lateral size TEM [21] SEM [21] AFM [24] Atomic C/O ratio XPS [13,16] Elemental analysis (ICP-MS) [25] [a] TEM: transmission electron microscopy, SEM: scanning electron microscopy, AFM: stomic force microscopy, ICP-MS: inductively coupled plasma mass spectrometry. Table 2: Potential benefits associated with adoption of GBM nomenclature.…”

Section: Discussionmentioning

confidence: 99%

Classification Framework for Graphene‐Based Materials

et al. 2014

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“…The G band corresponds to the E 2 g phonon at the Brillion zone center. The D band is due to the breathing modes of sp 2 atoms and requires a defect for its activation and it only gives knowledge to the amount of disorder in the given structure (Ferrari and Robertson 2000;Dhakate et al 2011). Figure 3b shows the Raman spectra of CF and CF-Ni, consisting of two bands D and G appearing at Raman shift 1,350 and 1,598 cm -1 , respectively.…”

Section: Characterizationmentioning

confidence: 99%

Nickel nanoparticles embedded in carbon foam for improving electromagnetic shielding effectiveness

2014

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To improve electromagnetic shielding effectiveness of light weight carbon foam (CF), magnetic nanoparticles were embedded in it during processing. The CF was developed from the coal tar pitch and mixture of coal tar pitch-Nickel (Ni) nanoparticles by sacrificial template technique and heat treated to up 1,000°C. To ascertain the effect of Ni nanoparticles embedded in CF, it was characterized by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, vector network analyzer and vibration sample magnetometer. It is observed that Ni nanoparticles embedded in the carbon material play an important role for improving the structure and electrical conductivity of CF-Ni by catalytic carbonization. The structural investigation suggests that the Ni nanoparticles embedded in the carbon material in bulk as well on the surface of CF. The CF demonstrates excellent shielding response in the frequency range 8.2-12.4 GHz in which total shielding effectiveness (SE) dominated by absorption losses. The total SE is -25 and -61 dB of CF and CF-Ni, it is governed by absorption losses -48.5 dB in CF-Ni. This increase is due to the increase in dielectric and magnetic losses of ferromagnetic Ni nanoparticles with high surface area. Thus, light weight CF embedded with small amount of magnetic nanoparticles can be useful material for stealth technology.

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An approach to produce single and double layer graphene from re-exfoliation of expanded graphite

Cited by 139 publications

References 42 publications

N₂‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO₂/Si Substrate Via the Langmuir–Blodgett Technique

N₂‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO₂/Si Substrate Via the Langmuir–Blodgett Technique

Classification Framework for Graphene‐Based Materials

Nickel nanoparticles embedded in carbon foam for improving electromagnetic shielding effectiveness

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An approach to produce single and double layer graphene from re-exfoliation of expanded graphite

Cited by 139 publications

References 42 publications

N2‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO2/Si Substrate Via the Langmuir–Blodgett Technique

N2‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO2/Si Substrate Via the Langmuir–Blodgett Technique

Classification Framework for Graphene‐Based Materials

Nickel nanoparticles embedded in carbon foam for improving electromagnetic shielding effectiveness

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Product

Resources

About

N₂‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO₂/Si Substrate Via the Langmuir–Blodgett Technique

N₂‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO₂/Si Substrate Via the Langmuir–Blodgett Technique