Raman spectrum of graphene and graphene layers.
TL;DR: This work shows that graphene's electronic structure is captured in its Raman spectrum that clearly evolves with the number of layers, and allows unambiguous, high-throughput, nondestructive identification of graphene layers, which is critically lacking in this emerging research area.
Abstract: Graphene is the two-dimensional building block for carbon allotropes of every other dimensionality We show that its electronic structure is captured in its Raman spectrum that clearly evolves with the number of layers The D peak second order changes in shape, width, and position for an increasing number of layers, reflecting the change in the electron bands via a double resonant Raman process The G peak slightly down-shifts This allows unambiguous, high-throughput, nondestructive identification of graphene layers, which is critically lacking in this emerging research area
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TL;DR: In this article, the tetraalkylammonium cations are intercalated into pristine graphite to form few-layer graphene flakes, which are then used for graphite rod electrode fabrication.
217 citations
Cites background from "Raman spectrum of graphene and grap..."
...[39] Ferrari AC, Meyer JC, Scardaci V, Casiraghi C, Lazzeri M, Mauri F, et al....
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TL;DR: In this article, the room temperature Raman signatures from graphene layers on sapphire and glass substrates were compared with those from graphene on GaAs substrate and on the standard Si/SiO2 substrate, which served as a reference.
Abstract: The room-temperature Raman signatures from graphene layers on sapphire and glass substrates were compared with those from graphene on GaAs substrate and on the standard Si/SiO2 substrate, which served as a reference. It was found that while G peak of graphene on Si/SiO2 and GaAs is positioned at 1580 cm -1 it is down-shifted by ~5 cm -1 for graphene-on-sapphire (GOS) and, in many cases, splits into doublets for graphene-on-glass (GOG) with the central frequency around 1580 cm -1 . The obtained results are important for graphene characterization and its proposed graphene applications in electronic devices.
217 citations
TL;DR: A new method for the synthesis of graphene films directly on SiO(2)/Si substrates, even plastics and glass at close to room temperature (25-160 °C), which opens up new possibilities for the fabrication of multiple nanoelectronic devices.
Abstract: Current methods for fabricating graphene rely on its transfer from metal surfaces to substrates suitable for device applications This study demonstrates a transfer-free approach for growing graphene on substrates such as thermally oxidized silicon and plastic that forms the material underneath a nickel film, at the nickel–substrate interface
216 citations
Cites background from "Raman spectrum of graphene and grap..."
...Although the line shape of the 2D band in Raman spectra of the graphitic layers provides a good measure to determine the number of layers due to the double resonance process [61], we do not consider this hallmark in our works because an ordered stacking (i....
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...4 in graphene layers grown at 160 °C, which are comparable to those of CVD-grown films at elevated temperature (~ 1000 °C) onto polycrystalline nickel surfaces [61]....
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TL;DR: In this paper, the authors report the fabrication of flexible conductive graphene paper through a direct and gentle annealing process of graphene oxide paper, which leads to a significant removal of disruptive oxygen-containing functional groups, and to a considerable recovery of the sp2 network structure.
216 citations
TL;DR: In this paper, the deposition of atomically thin highly uniform chemically derived graphene (CDG) films on 300 mm SiO(2)/Si wafers is reported, which can be lifted off to form uniform membranes that can be free-standing or transferred onto any substrate.
Abstract: The deposition of atomically thin highly uniform chemically derived graphene (CDG) films on 300 mm SiO(2)/Si wafers is reported. We demonstrate that the very thin films can be lifted off to form uniform membranes that can be free-standing or transferred onto any substrate. Detailed maps of thickness using Raman spectroscopy and atomic force microscopy height profiles reveal that the film thickness is very uniform and highly controllable, ranging from 1-2 layers up to 30 layers. After reduction using a variety of methods, the CDG films are transparent and electrically active with FET devices yielding high mobilities of approximately 15 cm(2)/(V s) and sheet resistance of approximately 1 kOmega/sq at approximately 70% transparency.
216 citations
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28 Jul 2005
TL;DR: PfPMP1）与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations