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 authors show that the Young's modulus and stress at 3% strain increase by ×100, saturating at 1 GPa and 25 MPa, respectively, for mass fractions above 50 kg.
283 citations
TL;DR: In this article, a flexible conductive cotton fabric was demonstrated by formulation and deposition of a graphene oxide (GO) dispersion onto a cotton fabric by vacuum filtration, and the deposited GO amount was controlled by the concentration and volume of the GO dispersion.
282 citations
TL;DR: A transfer-free method of synthesizing bilayer graphene directly on SiO(2) substrates by carbon diffusion through a layer of nickel is reported, eliminating any transfer process.
Abstract: Here we report a transfer-free method of synthesizing bilayer graphene directly on SiO2 substrates by carbon diffusion through a layer of nickel. The 400 nm nickel layer was deposited on the top of SiO2 substrates and used as the catalyst. Spin-coated polymer films such as poly(methyl methacrylate), high-impact polystyrene or acrylonitrile–butadiene–styrene, or gas-phase methane were used as carbon sources. During the annealing process at 1000 °C, the carbon sources on the top of the nickel decomposed and diffused into the nickel layer. When cooled to room temperature, bilayer graphene was formed between the nickel layer and the SiO2 substrates. The nickel films were removed by etchants, and bilayer graphene was then directly obtained on SiO2, eliminating any transfer process. The bilayer nature of the obtained graphene films on SiO2 substrates was verified by Raman spectroscopy and transmission electron microscopy. The Raman spectroscopy mapping over a 100 × 100 μm2 area indicated that the obtained graph...
282 citations
Cites background from "Raman spectrum of graphene and grap..."
...org 8243 transitions in graphene.(26) 29 The 2D peak position, fwhm, and shape, together with the G to 2D peak ratio, all indicate that PMMA-derived graphene on SiO2 is bilayered....
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TL;DR: In this paper, an epoxy-silicone matrix filled with both graphene nanosheets (GNs) and flake carbonyl iron (FCI) particles was prepared, and the influence of GNs and/or FCI particle content on the electromagnetic and microwave absorbing properties was investigated in the frequency range of 2-18 GHz.
281 citations
TL;DR: In this article, a metal-catalyzed crystallization of amorphous carbon to graphene by thermal annealing is demonstrated, where the thickness of the precipitated graphene is directly controlled by the initial amorphized carbon layer.
Abstract: Metal-catalyzed crystallization of amorphous carbon to graphene by thermal annealing is demonstrated. In this “limited source” process scheme, the thickness of the precipitated graphene is directly controlled by the thickness of the initial amorphous carbon layer. This is in contrast to chemical vapor deposition processes, where the carbon source is virtually unlimited and controlling the number of graphene layers depends on the tight control over a number of deposition parameters. Based on the Raman analysis, the quality of graphene is comparable to other synthesis methods found in the literature, such as chemical vapor deposition. The ability to synthesize graphene sheets with tunable thickness over large areas presents an important progress toward their eventual integration for various technological applications.
280 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