We produced carbon hybrid materials of graphene sheets decorated with metal or metal oxide nanoparticles of gold, silver, copper, cobalt, or nickel from cation exchanged graphite oxide. Measurements using powder X-ray diffraction, transmission electron microscopy, and X-ray absorption spectra revealed that the Au and Ag in the materials (Au-Gr and Ag-Gr) existed on graphene sheets as metal nanoparticles, whereas Cu and Co in the materials (Cu-Gr and Co-Gr) existed as a metal oxide. Most Ni particles in Ni-Gr were metal, but the surfaces of large particles were partly oxidized, producing a core-shell structure. The Ag-Gr sample showed a catalytic activity for the oxygen reduction reaction in 1.0 M KOH aq. under an oxygen atmosphere. Ag-Gr is superior as a cathode in alkaline fuel cells, which should not be disturbed by the methanol cross-over problem from the anode. We established an effective approach to prepare a series of graphene-nanoparticle composite materials using heat treatment ...
Flexible reduced graphene oxide (rGO) sheets are being considered for applications in portable electrical devices and flexible energy storage systems. However, the poor mechanical properties and electrical conductivities of rGO sheets are limiting factors for the development of such devices. Here we use MXene (M) nanosheets to functionalize graphene oxide platelets through Ti-O-C covalent bonding to obtain MrGO sheets. A MrGO sheet was crosslinked by a conjugated molecule (1-aminopyrene-disuccinimidyl suberate, AD). The incorporation of MXene nanosheets and AD molecules reduces the voids within the graphene sheet and improves the alignment of graphene platelets, resulting in much higher compactness and high toughness. In situ Raman spectroscopy and molecular dynamics simulations reveal the synergistic interfacial interaction mechanisms of Ti-O-C covalent bonding, sliding of MXene nanosheets, and π-π bridging. Furthermore, a supercapacitor based on our super-tough MXene-functionalized graphene sheets
Highly oriented pyrolytic graphite (HOPG) is a highly pure and ordered form of synthetic graphite. It is characterised by a low mosaic spread angle, meaning that the individual graphite crystallites are well aligned with each other. The best HOPG samples have mosaic spreads of less than 1 degree. It is used in x-ray optics as a monochromator and in scanning probe microscopy as a substrate and for magnification calibration. Note that the term highly ordered pyrolytic graphite is sometimes used for this material, but IUPAC favors highly oriented The method used to produce HOPG is based on the process used to make pyrolytic graphite, but with additional tensile stress in the basal plane direction. This produces improved alignment of the graphite crystallites, and an interplanar spacing close to that observed in natural graphite. The stress recrystallization of graphite was first described by L.C.F. Blackman and Alfred Ubbelohde in 1962 The diameters of the individual crystallites in HOPG are ...
RS Mines proudly presents its Natural 99%+ Carbon, highly ordered pyrolytic graphite or highly oriented pyrolytic graphite (HOPG), 300g nuggets It is now understood and verified that a small percentage, ~3% of output from The Queens Mine is HOP G - Highly ordered pyrolytic graphite or highly oriented pyrolytic graphite (HOPG). The physical properties of HOPG - Highly Ordered Pyrolytic Graphite
ZnO nanorods were grown on graphene oxide (GO) and reduced graphene oxide (RGO) films with seed layers by using simple hydrothermal method. The GO films were deposited by spray coating and then annealed at 400 degrees C in argon atmosphere to obtain RGO films. The optical and structural properties of the ZnO nanorods were systematically studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible spectroscopy. The XRD patterns and SEM images show that without a seed layer, no ZnO nanorod deposition occurs on GO or RGO films. Transmittance of ZnO nanorods grown on RGO films was measured to be approximately 83% at 550 nm. Furthermore, while transmittance of RGO films increases with ZnO nanorod deposition, transmittance of GO decreases. (C) 2011 Elsevier B. V. All rights reserved. ...
Graphene is a carbon based material that can be viewed as a one atom thick sheet of graphite and has been investigated intensely in recent years following a report by Novoselov et al. on its isolation and measurement of its unique electronic properties.1 Quickly after its initial discovery, graphene was used to make electronic devices for a variety of applications.2 Because high quality sheets of graphene is often prepared by chemical vapor deposition (CVD),3,4 which requires expensive equipment, many groups have looked at using graphene oxide as a solution processable alternative for the preparation of graphene like materials.5,6,7 Indeed, graphene oxide can be reduced in solution and as a thin film using a variety of reducing conditions, and reduction converts the graphene oxide into a material that has a large enhancement in electrical conductivity.7,8 In addition to its use in making reduced graphene oxide for electronic devices, graphene oxide
Woven graphite options for the Baja 5B off-road buggy not only look amazing, they strengthen and lighten your Baja 5B as well! Impressing your friends was never so easy - just bolt on these factory options for instant coolness and performance!. A full range of CNC machined, thick woven graphite options are available to fully outfit your Baja 5B, improving performance and durability at the same time. #87402 FRONT ARM BRACE SET (WOVEN GRAPHITE/BAJA 5B) #87405 REAR ARM BRACE SET (WOVEN GRAPHITE/BAJA 5B) #87444 REAR CHASSIS PLATE (WOVEN GRAPHITE/BAJA 5B) #87446 FRONT UPPER PLATE (WOVEN GRAPHITE/BAJA 5B) #87447 GEAR PLATE (WOVEN GRAPHITE/BAJA 5B) #87449 REAR BRACE (WOVEN GRAPHITE/BAJA 5B) #87453 REAR UPPER PLATE SET (WOVEN GRAPHITE/BAJA 5B) #87454 ENGINE MOUNT BRACE SET (WOVEN GRAPHITE/BAJA 5B). ...
You can imagine that these microscale sheets may be stacked together and chemically linked, allowing us to further optimize the mechanical properties of the resulting macroscale object, Ruoff says. This combination of excellent mechanical properties and chemical tunability should make graphene-based paper an exciting material.. Of further interest are the electrical properties of the graphene oxide paper in comparison to graphene sheets. When we oxidize the graphene sheets to create graphene oxide, the material goes from being an electrical conductor to an electrical insulator, Ruoff says. This is an important step and in the future it will be possible to tune the material as a conductor, semiconductor or insulator. One will be able to control the electrical properties without sacrificing exceptional mechanical properties.. Ruoff sees a wide variety of applications for graphene oxide paper, including membranes with controlled permeability, and for batteries or supercapacitors for energy ...
A solid state graphite electrode to determine the activity of an ion-specie in solution. The graphite electrode of the present invention can be adapted for use as either an external reference electrode, an ion-selective electrode or as an internal reference electrode. The electrode includes, as an electrically conductive element, a supported section of graphite that is appropriately electrically connected through a potentiometer to show a difference in ion concentration as a voltage potential or emf. One graphite surface for immersion in a test solution is hydrophobized by coating it with a solution that contains an organic liquid molecule to covalently bond with hydroxyl groups (OH) of the graphite surface, rendering that surface hydrophobic. Preferably, the organic liquid is a silanizing agent, which coating after drying is covered with a hydrophobic layer or membrane that is preferably a polyvinylchloride (PVC) plastic. For an ion-selective electrode, an ion sensor for the ion to be sensed is
Orient Carbon Industry is one the largest carbon, graphite electrode supplier and manufacturer in the north of China. They are the only products that can sustain high heat levels. Graphite electrodes come into RP Graphite electrodes, HP Graphite electrodes.
In this study, an electrochemical ascorbic acid (AA) sensor was constructed based on a glassy carbon electrode modified with palladium nanoparticles supported on graphene oxide (PdNPs-GO). PdNPs with a mean diameter of 2.6 nm were homogeneously deposited on GO sheets by the redox reaction between PdCl42- and GO. Cyclic voltammetry and amperometric methods were used to evaluate the electrocatalytic activity towards the oxidation of AA in neutral media. Compared to a bare GC or a Pd electrode, the anodic peak potential of AA (0.006 V) at PdNPs-GO modified electrode was shifted negatively, and the large anodic peak potential separation (0.172 V) of AA and dopamine (DA), which could contribute to the synergistic effect of GO and PdNPs, was investigated. A further amperometric experiment proved that the proposed sensor was capable of sensitive and selective sensing of AA even in the presence of DA and uric acid. The modified electrode exhibited a rapid response to AA within 5 s and the amperometric ...
We present a x-ray dichroism study of graphite surfaces that addresses the origin and magnitude of ferromagnetism in metal-free carbon. We find that, in addition to carbon {pi} states, also hydrogen-mediated electronic states exhibit a net spin polarization with significant magnetic remanence at room temperature. The observed magnetism is restricted to the top {approx}10 nm of the irradiated sample where the average magnetization reaches {approx_equal} 15 emu/g at room temperature. We prove that the ferromagnetism found in metal-free untreated graphite is intrinsic and has a similar origin as the one found in proton bombarded graphite. Also, our findings show that the magnetic properties of graphite surfaces, thin films or two dimensional graphene samples can be reliably studied using soft x-ray dichroism. Fundamental new insight into the magnetic properties of carbon based systems can thus be obtained.
Targeted delivery of reduced graphene oxide nanosheets using multifunctional ultrasound nanobubbles for visualization and enhanced photothermal therapy Zhao Liu,1,* Jia Zhang,2,* Yuhang Tian,1 Lei Zhang,1 Xue Han,1 Qiucheng Wang,1 Wen Cheng1 1Department of Ultrasound, Harbin Medical University Cancer Hospital, Nangang District, Harbin 150080, China; 2Key Laboratory of Microsystems and Microstructure Manufacturing, Ministry of Education, Harbin Institute of Technology, Harbin 150080, China *These authors contributed equally to this work Abstract: Ultrasound molecular imaging as a promising strategy, which involved the use of molecularly targeted contrast agents, combined the advantages of contrast-enhanced ultrasound with the photothermal effect of reduced graphene oxide (rGO). Methods and results: The heparin sulfate proteoglycan glypican-3 (GPC3) is a potential molecular target for hepatocellular carcinoma (HCC). In this study, we covalently linked biotinylated GPC3 antibody to PEGylated nano-rGO to
Why is diamond so hard?, Why is Graphite soft and Diamond hard if both are pure carbon? , This explains why diamonds are so hard and have such a high melting point [Diamond structure shown using the Jsmol] Try this!! , graphite has a low melting point d) none of the above 5 ,BBC News, Graphene is taken from graphite, which is made up of weakly bonded layers of carbon Graphene is composed of carbon atoms arranged in tightly bound hexagons just one atom thick Three million sheets of graphene on top of each other would be 1mm thickWhy does graphite have a high melting point even though ,, Now melting is essentially turning a highly ordered state of molecules to a disorderly one That comes at an expense of energy In this case, since the constituent molecules of graphite are held together by a strong covalent force, a high amount of energy is needed to weaken that bond That explains graphites high melting pointBonding Structures, The physical properties of graphite: Has a high melting point, similar ...
Flake Graphite. Flake graphite is a naturally occurring form of graphite that is typically found as discrete flakes ranging in size from 50-800 micrometers in diameter and 1-150 micrometers thick. This form of graphite has a high degree of crystallinity, which equates to near theoretical true density, high thermal and electric conductivity, and low springback (excellent molding characteristics).. Flake graphite is used in many applications including but not limited to powder metallurgy, fuel cell bi-polar plates, coatings, thermal materials, friction moderators, electrically conductive materials, refractories, general lubricant applications, pencils, gaskets, rubber compounds, and other advanced polymer systems. Commercial grades are available in purities ranging from 80-99.9% carbon, and sizes from 2-800 microns.. An In-Depth Description - Flake Graphite. Request a Sample. Amorphous Graphite. Amorphous graphite is a naturally occurring seam mineral that forms from the geologic metamorphism of ...
Graphite Oxide, which is produced by Royal Elite in a Lab scale via a modified Hummers, has good solubility in water, ethanol, DMF etc. It is a new carbon material with good properties. Graphite Oxide can be easily dispersed in polar solvents with the help of ultrasound and it can be applied in many fields, such as preparation of graphene; conductive graphene film; biochemical materials; transparent conductive coatings; nano electro devices; sensor and optics; catalyst and energy storage.. PROPERTIES:. Purity: 99%. Stacking Density: 0.8~1g/ml. Color: Brown solid. C/O Ratio: 1.35. ...
Fanny Hauquier, David Alamarguy, Sophie Noël, P. Viel. Evaluating Properties of Graphene Sheets using Conductive Probe Atomic Force Microscopy. MRS Fall Meeting, Nov 2009, Boston, United States. pp.K10.44. ⟨hal-00445400⟩ ...
A novel three-dimensional, interconnected conducting layer network, comprised of crumpled nitrogen- and boron-dual-self-doped graphene sheets (NBGs) with an ultrahigh content of 7.72 at% nitrogen and 7.18 at% boron, has been synthesized through one-step thermolysis, using a borane-tert-butylamine complex as
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A variety of distinctive techniques have been developed to produce graphene sheets and their functionalized subsidiaries or composites. The production of graphene sheets by oxidative exfoliation of graphite can be a suitable route for the preparation of high volumes of graphene derivatives. P-substituted graphene material is developed for its application in hydrogen sorption in room temperature. Phosphorous doped graphene material with multi-layers of graphene shows a nearly ~2.2 wt% hydrogen sorption capacity at 298 K and 100 bar. This value is higher than that for reduced graphene oxide (RGO without phosphorous).
Graphite, which consists of layers of carbon atoms arranged in hexagonal lattices, can superconduct when doped with elements that provide it with additional free electrons. Calcium graphite, for example, superconducts at up to 11.5 kelvin (about -260 °C)2, and theorists have predicted that temperatures of up to 60 kelvin could be reached if enough free electrons were available.. Esquinazis team speculates that high concentrations of electrons form at the interfaces between neighbouring thin segments of graphite. Having already observed superconductivity at more than 100 kelvin at the interfaces within an artificial type of bulk graphite known as pyrolytic graphite3, the researchers wondered whether they could reach even higher temperatures by doping flakes of graphite powder.. The first dopant they tried was ordinary water. They got lucky. They placed 100 milligrams of pure graphite powder made up of flakes a few hundredths of a millimetre long and tens of nanometres thick into 20 millilitres ...
Title:Microwave Assisted Exfoliation of Graphene and its Application in Enzyme Immobilization. VOLUME: 1 ISSUE: 3. Author(s):Mahe Talat, Kalpana Awasthi and Onkar N. Srivastava. Affiliation:Nanoscience and Nanotechnology Unit, Department of Physics, Banaras Hindu University, Varanasi- 221005. Keywords:Graphene oxide, microwave irradiation, enzyme, immobilization, energy saving, urease enzyme.. Abstract:Background: Few layer graphene oxide was prepared by microwave irradiation which is convenient and less energy-consuming method. The enzyme immobilized graphene can be used for various applications including in the field of industrial, biomedical, waste-water treatment etc. Objective: The aim of the present study is to prepare graphene using fast and energy saving method and immobilization of Urease enzyme onto functionalized graphene sheet for various applications. Method: Few layer graphene oxides were prepared by microwave irradiation of graphite oxide. The graphene oxide was functionalized by ...
Magnetite, Fe3O4, is a promising anode material for lithium ion batteries due to its high theoretical capacity (924 mA h g−1), high density, low cost and low toxicity. However, its application as high capacity anodes is still hampered by poor cycling performance. To stabilize the cycling performance of Fe3O4 nanoparticles, composites comprising Fe3O4 nanoparticles and graphene sheets (GS) were fabricated. The Fe3O4/GS composite disks of mm dimensions were prepared by electrostatic self-assembly between negatively charged graphene oxide (GO) sheets and positively charged Fe3O4-APTMS [Fe3O4 grafted with (3-aminopropyl)trimethoxysilane (APTMS)] in an acidic solution (pH = 2) followed by in situ chemical reduction. Thus prepared Fe3O4/GS composite showed an excellent rate capability as well as much enhanced cycling stability compared with Fe3O4 electrode. The superior electrochemical responses of Fe3O4/GS composite disks assure the advantages of: (1) electrostatic self-assembly between high storage
Graphene1-3 possesses a unique application potential, such as in electronic devices,4,5 sensors6,7 and lithium ion batteries,8,9 owing to its remarkable electronic properties. The functionalization of pristine graphene by chemical and physical methods is crucial for broadening its application range by generating new properties.10 For instance, oxidized graphene or graphene oxide (GO) is more reactive than graphene11-15 and highly water-dispersible,16,17 making it a promising scaffold material for drug delivery,18 sensing,19,20 catalysis,21,22 imaging,23-25 substrates for implants26 and low-cost production of large quantities of graphene and graphene-based materials.27-29 GO is a structurally complex material whose nature depends on the oxidation method used.30 The surface of GO consists of randomly dispersed graphitic and oxidized regions covered by epoxy and hydroxyl groups. Other functional groups, such as carboxyl, quinone, ketone and peroxide, may also be present.12,31,32 Owing to its random ...
Large-Scale Pattern Growth of Graphene Films for Stretchable Transparent Electrodes. Nature 457, 706 (2009) Problems associated with large-scale pattern growth of graphene constitute one of themain obstacles to using thismaterial in device applications1. Recently, macroscopic-scale graphene films were prepared by two-dimensional assembly of graphene sheets chem-ically derived from graphite crystals and graphene oxides2,3 . However, the sheet resistance of these films was found to be much larger than theoretically expected values. Here we report the direct synthesis of large-scale graphene films using chemical vapour deposition on thin nickel layers, and present two differentmethods of patterning the films and transferring them to arbitrary substrates. The transferred graphene films show very low sheet resistance of 280Vper square, with 80 per cent optical transparency...... ...
The adsorption and growth of 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) on graphene monolayers epitaxially grown on Pt(111) surfaces is studied by a combination of experimental scanning tunneling microscopy (STM) and spectroscopy (STS) measurements and first-principles density functional theory (DFT) calculations. For submonolayer coverage, until the completion of the first layer, PTCDA molecules form a well-ordered herringbone structure with molecules lying flat on the graphene surface weakly coupled to the Pt(111) substrate. High-resolution STM imaging at different sample biases has allowed the identification of intramolecular features that can be related to the original PTCDA frontier orbitals. Theoretical STM calculations, based on local-orbital DFT, have been carried out on the full PTCDA/graphene/Pt(111) system. The comparison of theoretical and experimental STM images has allowed us to ascribe the origin of intramolecular features to the highest occupied and lowest unoccupied molecular
CarboGraphite Group was establishe in 1992, 27 years of production experience,which is one of the earliest and biggest suppliers of high-quality Graphite Electrode and carbon products in China.Which is specialized in R&D, manufactures and sales of various graphite electrodes. Including Electrodes For Sales Uhp,Uhp Graphite Electrode With Nipples,UHP Graphite Electrode,Price Uhp Graphite Electrode,Graphite Electrode Uhp For Arc Furnace, Uhp Graphite Electrode Spot. The company has a production capacity of 50,000 tons of graphite electrode,200,000 tons of Electrode Paste,150,000 tons of refined petroleumcoke,100,000 tons of pre-baked anode, 50,000 tons of carbon brick,special sealing paste, 50,000 tons of Refractory material. Our company has domestic advanced quality inspection system and perfect after-sales service team, to the masses of customers to provide quality products and good technical services, and is willing to cooperate sincerely with new and old friends. Raw Materials:Needle ...
Australian graphite stocks have experienced a veritable boost in the past few weeks as many more companies have joined the graphite industry in expectation of much higher demand for Lithium-ion batteries (which, despite their name, use more graphite than lithium). Including China, the graphite sector now includes eight countries and there are promising resources being developed in Canada, the USA, Madagascar, Sri Lanka and Sweden among others. Naturally, there are concerns - and justified ones - that nobody knows where the volume of graphite demand will be heading in the future. Indeed, the graphite market is not all that big now and caution is well, almost always useful. The bets are that those companies that can produce high levels of purity will have a huge competitive advantage and the market will surely weed out the number of graphite companies as the realities of establishing a solid customer base and delivering consistent high quality at low cost take over. The current purity standard for ...
It adheres to your tenet Honest, industrious, enterprising, innovative to produce new solutions constantly. It regards consumers, success as its own success. Let us develop prosperous future hand in hand for Rp Artificial Graphite Electrodes , RP Artificial Graphite Electrodes , Artificial Graphite Electrodes , We hope to have long-term cooperation relationships with our clients. If you are interested in any of our products and solutions please do not hesitate to send enquiry to us/company name. We ensure that you can be totally satisfied with our best solutions ...
University of Manchester scientists have studied membranes from a chemical derivative of graphene called graphene oxide. Graphene oxide is the same graphene sheet but it is randomly covered with other molecules such as hydroxyl groups OH-. Graphene oxide sheets stack on top of each other and form a laminate.. The researchers prepared such laminates that were hundreds times thinner than a human hair but remained strong, flexible and were easy to handle.. When a metal container was sealed with such a film, even the most sensitive equipment was unable to detect air or any other gas, including helium, to leak through.. It came as a complete surprise that, when the researchers tried the same with ordinary water, they found that it evaporates without noticing the graphene seal. Water molecules diffused through the graphene-oxide membranes with such a great speed that the evaporation rate was the same independently whether the container was sealed or completely open.. Dr Rahul Nair, who was leading the ...
Graphite/epoxy composites have the potential to be used as conductive polymer composites (CPCs). Nevertheles, graphite/epoxy composites have a low in-plane conductivity, so a large amount of conductive filler is needed to increase the in-plane conductivity. However, other composite properties can be affected if the conductive filler content is too high. The casting method was used to produce graphite/epoxy composites in this study. Graphite was added to an epoxy resin at various weight percentage (wt%), curing times, and curing temperatures. The result show that a graphite/epoxy composite with 80 wt% of graphite at curing temperature of 130 ℃ and a curing time of 120 minutes produce the highest in-plane conductivity and shore hardness of 28 S/cm and 94.88 SHD, respectively. In contrast, the highest tensile strength of the graphite/epoxy composite (18.5 N/mm|sup|2|/sup|) was obtained with 65 wt% of conductive filler material, the lowest amount considered in this study. This is due to the reduced
Graphitic carbon is currently considered the state-of-the-art material for the negative electrode in lithium ion cells, mainly due to its high reversibility and low operating potential. However, carbon anodes exhibit mediocre charge/ discharge rate performance, which contributes to severe transport-induced surface structural damage upon prolonged cycling and limits the lifetime of the cell. Lithium bulk diffusion in graphitic carbon is not yet completely understood, partly due to the complexity of measuring bulk transport properties in finite-sized nonisotropic particles. To solve this problem for graphite, we use the DevanathanStachurski electrochemical methodology combined with ab initio computations to deconvolute and quantify the mechanism of lithium ion diffusion in highly oriented pyrolytic graphite (HOPG). The results reveal inherent high lithium ion diffusivity in the direction parallel to the graphene plane (∼10-7 -10-6 cm2 s -1 ), as compared to sluggish lithium ion transport along ...
One of the advantages of the gaphene oxide is its easy dispersability in water and other organic solvents, as well as in different matrixes, due to the presence of the oxygen functionalities. This remains as a very important property when mixing the material with ceramic or polymer matrixes when trying to improve their electrical and mechanical properties.. On the other hand, in terms of electrical conductivity, graphene oxide is often described as an electrical insulator, due to the disruption of its sp2 bonding networks. In order to recover the honeycomb hexagonal lattice, and with it the electrical conductivity, the reduction of the graphene oxide has to be achieved. It has to be taken into account that once most of the oxygen groups are removed, the reduced graphene oxide obtained is more difficult to disperse due to its tendency to create aggregates.. Functionalization of graphene oxide can fundamentally change graphene oxides properties. The resulting chemically modified graphenes could ...
Graphene oxide potentially has multiple applications. The chemistry of graphene oxide and its response to external stimuli such as temperature and light are not well understood and only approximately controlled. This understanding is crucial to enable future applications of this material. Here, a combined experimental and density functional theory study shows that multilayer graphene oxide produced by oxidizing epitaxial graphene through the Hummers method is a metastable material whose structure and chemistry evolve at room temperature with a characteristic relaxation time of about one month. At the quasi-equilibrium, graphene oxide reaches a nearly stable reduced O/C ratio, and exhibits a structure deprived of epoxide groups and enriched in hydroxyl groups. Our calculations show that the structural and chemical changes are driven by the availability of hydrogen in the oxidized graphitic sheets, which favours the reduction of epoxide groups and the formation of water molecules. Graphene oxide could
Hybridization of nucleic acids with graphene nanomaterials is of great interest due to its potential application in genosensing and nanomedicine. In this work we study the interaction between polyribocytidylic acid (poly(rC)) and graphene oxide (GO). The study involves comparing the UV absorption spectra of the free polymer and the polymer bonded to graphene oxide and analyzing the vibrational structure of the systems and their components using FTIR spectroscopy. Spectral shifts of the electronic and vibrational bands of the poly(rC) and changes of their thermostability due to the adsorption on GO are observed. Molecular dynamics simulation of the adsorption process of the r(C)10 and r(C)30 oligomers on graphene demonstrates their disordering due to the π-π stacking of cytosine on graphene and shows that the longer oligomer adsorbs slower. The binding energies of a single cytosine stacked with graphene in water and in vacuum were determined. The calculated IR lines of the stacked cytosine with ...
TY - GEN. T1 - Evaluation of an affinity-amplified immunoassay of graphene oxide using surface plasmon resonance biosensors. AU - Chiu, Nan-Fu. AU - Huang, Teng Yi. AU - Kuo, Chun Chuan. PY - 2015/1/1. Y1 - 2015/1/1. N2 - We describe a fundamental study on the plasmonic properties and advanced biosensing mechanisms of functionalized graphene. We discuss a specific design using modified carboxyl groups, which can modulate surface plasmon (SP) coupling and provide an advantage for their binding to the sensing layer with high-performance affinity in an immunological reaction. The functionalized graphene-based surface plasmon resonance (SPR) biosensors have three advantages: high performance, high sensitivity, and excellent molecular kinetic response. In the future, functionalized graphene sheets will make a unique contribution to photonic and SPR diagnosis devices. We wish to highlight the essential characteristics of functionalized graphene-based SPR biosensors to assist researchers in developing ...
A catalyst consisting of palladium - nickel supported on exfoliated graphene oxide (PdNi/EGO) composite was synthesized. The catalytic activity was tested for ethanol oxidation reaction (EOR) in half-cell using cyclic voltammetry (CV) and subsequently it was used as an anode material in a direct ethanol fuel cell (DEFC). Transmission Electron Microscopy showed the catalyst particles are uniformly dispersed on the surface of graphene oxide with the particle size ranging from 3 to 6 nm. X-ray Photoelectron Spectroscopy analysis of catalysts revealed that the surface consisting of mostly Pd, PdO, Ni(OH)2, and NiOOH. CV and chronoamperometry measurements demonstrated higher electrocatalytic activity and stability for PdNi/EGO in the alkaline medium than the unsupported PdNi and carbon black-supported PdNi (PdNi/C) catalysts. A single cell anion exchange membrane DEFC constructed with a PdNi/EGO anode catalyst showed a maximum power density of 16.6 m Wcm−2 at 50 °C, which is higher than the ...
Graphene nanoribbons (GNRs, also called nano-graphene ribbons or nano-graphite ribbons) are strips of graphene with width less than 50 nm. Graphene ribbons were introduced as a theoretical model by Mitsutaka Fujita and coauthors to examine the edge and nanoscale size effect in graphene. Large quantities of width-controlled GNRs can be produced via graphite nanotomy, where applying a sharp diamond knife on graphite produces graphite nanoblocks, which can then be exfoliated to produce GNRs. GNRs can also be produced by unzipping or axially cutting nanotubes. In one such method multi-walled carbon nanotubes were unzipped in solution by action of potassium permanganate and sulfuric acid. In another method GNRs were produced by plasma etching of nanotubes partly embedded in a polymer film. More recently, graphene nanoribbons were grown onto silicon carbide (SiC) substrates using ion implantation followed by vacuum or laser annealing. The latter technique allows any pattern to be written on SiC ...
This report reviews literature on reprocessing high temperature gas-cooled reactor graphite fuel components. A basic review of the various fuel components used in the pebble bed type reactors is provided along with a survey of synthesis methods for the fabrication of the fuel components. Several disposal options are considered for the graphite pebble fuel elements including the storage of intact pebbles, volume reduction by separating the graphite from fuel kernels, and complete processing of the pebbles for waste storage. Existing methods for graphite removal are presented and generally consist of mechanical separation techniques such as crushing and grinding chemical techniques through the use of acid digestion and oxidation. Potential methods for reprocessing the graphite pebbles include improvements to existing methods and novel technologies that have not previously been investigated for nuclear graphite waste applications. The best overall method will be dependent on the desired final waste ...
Graphite. False-colour scanning electron micrograph of scratches on the surface of a lubricating film of graphite. Graphite is a soft, slippery, crystalline form of carbon, widely used as a lubricant. It is applied to a surface in the form of an aqueous colloid (small particles of graphite suspended in water) & allowed to dry. The graphite forms a continuous sheet covering the surface & is gradually abraded as other parts rub against it. The lubricating nature of graphite is due to its molecular structure. The carbon atoms are arranged in arrays of flat hexagons, forming flakey plates (as seen here), which slip easily across each other. Mag: x300 at 35mm size. - Stock Image A150/0089
Ah, I see: I had compiled gcc-4.8.{0,1}* with graphite, of course. Maybe this is the reason for my many problems with graphite. On the other hand, it would be a strange accident that using gcc compiled with graphite just has problems for compiling with graphite. But who knows: Maybe the cause is that something in graphite is not reentrant or thread-safe and using graphite with a graphite-compiled gcc just forces such a behavior? ...
The unique two-dimensional (2D) structure and chemical properties of graphene and its derivatives make it a distinctive nanoscale building block for constructing novel bulky architectures with different dimensions, such as 1D fibers, 2D films and 3D architectures. These bulky graphene materials, depending on the manner in which graphene sheets are assembled, show a variety of fascinating features that cannot be achieved from individual graphene sheet or conventional materials. Thus, over the past several years, considerable effort has been expended in fabricating various structures of bulky graphene materials and developing their corresponding applications. Here, we present a broad and comprehensive overview of the recent developments in expanding the structural diversity of bulky graphene materials and their applications in energy storage and conversion, composites, environmental remediation, etc. Finally, prospects and further developments in this exciting field of bulky graphene materials are ...
Guanine adsorbed onto a highly oriented pyrolytic graphite electrode was studied by MAC-Mode Atomic Force Microscopy (AFM), and the electrochemical behaviour of the guanine layer was investigated with Electrochemical AFM. Guanine adsorbs spontaneously, without forming a well-packed structure, into nucleation spots, which are stable with time and cover the surface uniformly and almost completely. The process of guanine adsorption and nucleation can be controlled and the effect of altering the exposure time and varying the potential was investigated ...
Graphene has become one of the most widely studied 2D materials since its separation by Geim-Novoselov in 2004. It has been used in a wide range of applications due to its incredible carrier mobility, mechanical strength and thermal conductivity. The applications of graphene are ranging from electronics to energy storage and conversion. Chemical vapor deposition (CVD) is a common method for growing graphene on a metal surface as a catalyst, since it promotes growth of large area and high uniform graphene film. This requires an additional step to transfer graphene onto other target substrates toward fabrication of graphene-based devices. Graphene transfer process comprises many challenges such as presence of polymeric/metal residuals, generation of several extrinsic defects (tears, cracks and wrinkles) and weak adhesion between graphene and underlying target substrate. All these kinds of imperfections degrade graphene properties and hence affect the performance of the fabricated graphene-based ...
TY - JOUR. T1 - Graphene oxide. T2 - Surface activity and two-dimensional assembly. AU - Kim, Franklin. AU - Cote, Laura J.. AU - Huang, Jiaxing. PY - 2010/5/4. Y1 - 2010/5/4. N2 - Graphene oxide (GO) is a promising precursor for preparing graphene-based composites and electronics applications. Like graphene, GO is essentially one-atom thick but can be as wide as tens of micrometers, resulting in a unique type of material building block, characterized by two very different length scales. Due to this highly anisotropic structure, the collective material properties are highly dependent on how these sheets are assembled. Therefore, understanding and controlling the assembly behavior of GO has become an important subject of research. In this Research News article the surface activity of GO and how it can be employed to create two-dimensional assemblies over large areas is discussed.. AB - Graphene oxide (GO) is a promising precursor for preparing graphene-based composites and electronics ...
E1834-18 Standard Test Method for Analysis of Nickel Alloys by Graphite Furnace Atomic Absorption Spectrometry lead content~ graphite furnace atomic absorption spectrometry~
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We perform first-principles structure optimization, phonon frequency, and finite temperature molecular dynamics calculations based on density functional theory to study the interaction of chlorine atoms with graphene predicting the existence of possible chlorinated graphene derivatives. The bonding of a single chlorine atom is ionic through the transfer of charge from graphene to chlorine adatom and induces negligible local distortion in the underlying planar graphene. Different from hydrogen and fluorine adatoms, the migration of a single chlorine adatom on the surface of perfect graphene takes place almost without barrier. However, the decoration of one surface of graphene with Cl adatoms leading to various conformations cannot be sustained due to strong Cl-Cl interaction resulting in the desorption through the formation of Cl2 molecules. On the contrary, the fully chlorinated graphene, chlorographene CCl, where single chlorine atoms are bonded alternatingly to each carbon atom from different ...
The quite efficient adsorption of methylene blue dye from an aqueous solution by graphene oxide was studied. The favorable electrostatic attraction is the main interaction between methylene blue and graphene oxide. As graphene oxide has the special nanostructural properties and negatively charged surface, the positively charged methylene blue molecules can be easily adsorbed on it. In the aqueous solution of methylene blue at 293 K, the adsorption data could be fitted by the Langmuir equation with a maximum adsorption amount of 1.939 mg/mg and a Langmuir adsorption equilibrium constant of 18.486 mL/mg. The adsorption amount increased with the increase of the solution pH (3-11), was not affected significantly by KCl under the examined condition and the adsorption process was exothermic in nature. The fast and considerable adsorption of graphene oxide could be regarded as a potential adsorbent for cationic dye removal in wastewater treatment process ...
Diamond is composed of sp3 hybridized carbon atoms that are a very stable allotrope of carbon. Graphite is composed of sp2 hybridized carbon atoms and is an allotrope of carbon. Diamond is a cоlоrlеѕѕ trаnѕраrеnt ѕubѕtаnсе with extra оrdinаrу brilliаnсе due tо itѕ high refractive indеx. Graphite is a grеуiѕh black, ораԛuе substance. Diamond does not conduct electricity due to the absence of free ions. Graphite is a gооd conductor оf еlесtriсitу due to рrеѕеnсе of frее ions but bad соnduсtоr of heat. Diamond is the hardest mineral found in the world and is utilized as abrasives to cut and polish other products as well as gems. Graphite is the softest mineral and used for making lead pencils. In jewelry, accessories, and crowns; diamond is used as a gem. In its powdered form graphite is used as a lubricant for heavy pieces of equipment. Diamond is very hard and has numerous industrial applications as a tool to cut glass and to pierce hard rocks. ...
By charge neutralization of carboxylic acid groups in graphene oxide (GO) with Cs(2)CO(3) to afford Cesium-neutralized GO (GO-Cs), GO derivatives with appropriate modification are used as both hole- and electron-extraction layers for bulk heterojunction (BHJ) solar cells. The normal and inverted devices based on GO hole- and GO-Cs electron-extraction layers both outperform the corresponding standard BHJ solar cells.
Noller, BN (1978) Development and some applications of techniques for the determination of trace metals by furnace atomic absorption spectrometry. PhD thesis, University of Tasmania. ...
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graphene transistors, graphene field-effect transistors, state-of-the-art silicon transistors, vastly faster transistors, radio-frequency graphene transistor, ibm researchers, cut-off frequency, CERA transistors, gate length, high-quality graphene wafers, graphene device, fast power transistor, novel graphene films, graphene-based transistors, Elevelop wafer-scale graphene, highest cut-off frequency, CERA program, high cutoff frequencies, high performance W-band, YORKTOWN HEIGHTS, novel gate insulator, high integration potential, high saturation velocity, IBM T. J., relative thing, RF Applications, metal top-gate architecture, Carbon Electronics, RF system-on-chip applications, non-silicon electronic material, desirable material properties, dielectric constant oxide, natural graphite, unusual electronic properties, graphene flakes, traditional CMOS processes, Waston Research Center, immense worldwide attention, low parasitic resistances, generation electronic chips, low-power graphene-channel ...
The incorporation of well-dispersed graphene oxide (GO) and graphene (G) has been demonstrated as a promising solution to improve the mechanical performance of polymethyl methacrylate (PMMA) bone cements in an attempt to enhance the long-term survival of the cemented orthopaedic implants. However, to move forward with the clinical application of graphene-based PMMA bone cements, it is necessary to ensure the incorporation of graphene-based powders do not negatively affect other fundamental properties (e.g., thermal properties and biocompatibility), which may compromise the clinical success of the implant. In this study, the effect of incorporating GO and G on thermal properties, biocompatibility, and antimicrobial activity of PMMA bone cement was investigated. Differential scanning calorimetry studies demonstrated that the extent of the polymerisation reaction, heat generation, thermal conductivity, or glass transition temperature were not significantly (p > 0.05) affected by the addition of the ...
The improvement of LiFePO{sub 4} (LFP) cathode performance has been performed by addition of Graphene (LFP+Graphene). The cathode was prepared from the active material with 5 wt % graphene and 10 wt % polyvinylidene fluoride in an n-methyl pyrrolidone solvent. Another cathode material used only 5% artificial graphite for comparison (LFP+Graphite). The crystal structure, microstructure, electronic conductivity, electrochemical impedance spectroscopy (EIS) of the cathodes were characterized by X-ray diffraction, SEM, and Impedance spectroscopy, respectively. Two half cell coin batteries were assembled using a lithium metal as an anode and LiPf{sub 6} as an electrolyte, and two cathodes (LFP+Graphene) and (LFP+Graphite). Charge discharge performance of battery was characterized by Battery analyser (BTS 8). The electronic conductivity of cathode with grapheme increased of about one order magnitude compared with the only cathode with graphite, namely from 1.97E-7S/cm (LFP+Graphite) to 1.92E-6S/cm ...
The photoinduced growth reaction of silver nanoparticles was accelerated by reduced graphene oxide (RGO) produced from graphene oxide (GO) during the light irradiation process in aqueous solution. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy demonstrated that RGO was generated in the photoinduced process. The acceleration effect of RGO was investigated through monitoring the extinction spectra of silver nanoparticles during the synthesis process. Moreover, transmission electron microscopy (TEM) was employed to characterize the evolution of morphologies of silver nanoparticles at different irradiation times to demonstrate the effect of RGO. The results indicate that RGO accelerates the photoinduced synthesis of silver nanoparticles. It is proposed that the acceleration effect of RGO on the photoinduced reaction is attributed to the particular property of high electronic conductivity ...
Watch this video to learn about Analytic Jenas ZEEnit series of graphite furnace atomic absorption spectrometers with Zeeman background correction. Discover how the features of the ZEEnit allow precise and reproducible results to be obtained immediately.
Metal-oxide semiconductor field-effect transistor (MOSFET) scaling throughout the years has enabled us to pack million of MOS transistors on a single chip to keep in pace with Moores Law. After forty years of advances in integrated circuit (IC) technology, the scaling of silicon (Si) MOSFET has entered the nanometer dimension with the introduction of 90 nm high volume manufacturing in 2004. The latest technological advancement has led to a low power, high-density and high-speed generation of processor. Nevertheless, the scaling of the Si MOSFET below 22 nm may soon meet its fundamental physical limitations. This threshold makes the possible use of novel devices and structures such as carbon nanotube field-effect transistors (CNTFETs) and graphene nanoribbon field-effect transistors (GNRFETs) for future nanoelectronics. The investigation explores the potential of these amazing carbon structures that exceed MOSFET capabilities in term of speed, scalability and power consumption. The research ...
In this study, we report a facile approach to prepare dense arrays of MoS2 nanoribbons by combining procedures. of micromolding in capillaries (MIMIC) and thermolysis of thiosalts ((NH4)(2)MoS4) as the printing ink. The obtained MoS2 nanoribbons had a thickness reaching as. low as 3.9 nm, a width ranging from 157 to 465 nm, and a length up to 2 cm. MoS2 nanoribbons with an extremely high aspect ratio (lengthiwidtfi) of similar to 7.4 X 10(8) were achieved. The MoS2 pattern can be printed on versatile substrates, such as SiO2/Si, sapphire, Au film, FTO/glass, and graphene-coated glass. The degree of crystallinity of the as-prepared MoS2 was discovered to be adjustable by varying the temperature through postannealing. The high-temperature thermolysis (1000 degrees C) results in high-quality conductive samples, and field-effect transistors, based on the patterned MoS2 nanoribbons were demonstrated and characterized, where the carrier mobility was comparable to that of thin-film MoS2. In
Carbonaceous materials are considered as potential adsorbents for organic dyes due to their unique structures which provide high aspect ratios, hydrophobic property, large efcient surface area, and easy surface modifcation. In this work, graphene nanoribbons (GNRs) were prepared by atomic hydrogen-induced treatment of single-walled carbon nanotube (SWCNTs), which inspire the idea of cutting and unzipping the SWCNTs carpets with the modifed in molecules prevent because of the unfolding of the sid
IBM researchers have discovered a way to massively improve the performance of transistors made out of sheets of the two-dimensional carbon material graphene: they stack them up. By placing two layers of graphene on top of each other, they found that they can reduce the electrical noise of the device by a factor of 10.. The findings could help realize graphene-based chips that run faster, are more compact, and consume less power than todays silicon chips, says Yu-Ming Lin, a scientist at the IBM T. J. Watson Research Center, in Yorktown Heights, NY. IBM researchers are also investigating other promising successors to silicon, such as graphene-like carbon nanotubes. Graphene, which is made entirely out of carbon atoms arranged in a one-atom-thick honeycomb structure, has a number of properties that make it attractive for electronics, particularly for transistors that produce radio-frequency signals. But transistors created from the material have been plagued by noise, making the signals they ...
Graphene, a 2D honeycomb lattice of sp² hybridized carbons, has attracted the attention of the scientific community not only for its interesting theoretical properties but also for its myriad of possible applications. The discovery of graphene led to the Nobel Prize in physics for 2010 to be awarded to Andrei Geim and Konstantin Novoselov. Since its discovery, many methods have been developed for the synthesis of this material. Two of those methods stand out for the growth of high quality and large area graphene sheets, namely, epitaxial growth from silicon carbide (SiC) and chemical vapor deposition (CVD). As it stands today, both methods make use of high concentrations of hydrogen (10-20%) in N₂ or Ar, high temperatures, and a vacuum system. Epitaxial growth from SiC in addition requires very expensive single crystal SiC wafers. In the case of CVD, organic molecules are used as the carbon source to grow graphene on a metal substrate. Although graphene has been grown on many metal ...
A kind of molecular-level dispersed and highly oriented graphene monolayer nanocomposite film was successfully obtained by in situ reduction of phenyl isocyanate functionalized graphite oxide (RPIGO) in N,N-dimethylformamide in the presence of polystyrene (PS). Atomic force microscopy and transmission electron microscopy results show that the RPIGO monolayers were not only homogeneously intercalated into the PS matrix but also arranged parallel to the surface of the nanocomposite films. Because of the efficient interaction between the graphene monolayers and PS matrix, the mechanical properties of the graphene-based nanocomposite films improved significantly. Compared with the pure PS film, a 28.4% increase in the Youngs modulus and a 27.8% improvement in the tensile strength of the RPIGO-PS nanocomposites films were obtained with the addition of only 0.5 wt % graphite oxide. The glass-transition temperature and onset degradation temperature of PS also increased from 96.6 and 427°C to 103.2 ...
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Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. (See Table 2 above for Reserves). Lithium Battery Coin Cell Test Results On May 27th, Focus Graphite announced it Succeeded in Producing Extremely High-Performing Coated Spherical Graphite for Lithium Ion Batteries. The results from coin cell performance testing performed on Lac Knife Spherical Graphite (SPG) produced outstanding performance metric results. The benchmark products have a typical irreversible capacity loss (ICL) of 6-10% ICL. Lac Knife SPG showed two ICL test results measuring 1.01% and 1.44%, truly remarkable results. Essentially these battery performance tests illustrated that the Irreversible Capacity Loss (ICL) was reduced by 75% compared to the benchmark products available in the market today. These tests confirm Focus capability to tailor lithium ion battery anode grade SPG and value added products to meet the most stringent customer specifications Lac Knife anode SPG is ...
LAS VEGAS, Sept. 12, 2012 /PRNewswire/ -- National Graphite Announces Completion Of Geophysics Survey On Nevada Graphite Property.
Carbon plays a significant role in the development of electrode materials used in, for example, catalysis, energy storage and sensing. Graphene-based coatings and carbon nanotubes have expanded that role through nanostructuring of hybrids or the formation of composites. In particular, the formation of hybrids of nanocarbons with iridium oxide yield nanostructured materials through direct anodic deposition, which have substantially improved charge capacities vs. pure IrOx. Modification of the possible redox sites, new structuring of the hybrids and increased charge capacities are expected as a result. This work shows that nitrogen (N)-doped graphenes, as part of an IrOx hybrid, offer a new redox chemistry on graphene oxide through electrochemical modulation of the redox states of nitrogen in graphene, and yield stable nitro groups bound to carbon, which have, so far, the largest oxidation state reported in N-doped graphene. The hybrid materials are obtained in the form of coatings thanks to ...
A biosorption procedure for separation-enrichment of aluminum in environmental samples has been presented in this work. Pseudomonas aeruginosa loaded on Chromosorb 106 has been used as biosorbent for that purpose. P. aeruginosa is a gram-negative, aerobic rod. The influences of pH of the aqueous solution, eluent type, eluent volume, sample volume, etc. were examined on the quantitative recovery of aluminum in R aeruginosa loaded on Chromosorb 106. The effects of concomitant ions on the recoveries of aluminum were also investigated. The detection limit based on 3 sigma for aluminum is 30 ng L(-1). Three certified reference materials (LGC 6010 Hard Drinking Water, NIST-SRM 1568a Rice Flour and NRCC-DORM-2 Dogfish Muscle) were analyzed for the validation of the presented procedure. The proposed procedure was applied to the determination of aluminum in environmental samples including natural water and food samples. The concentration of aluminum in real samples was found at ppb level. (C) 2007 ...
A system has been designed and constructed to produce diamond particles by inductively coupled radio-frequency, plasma-assisted chemical vapor deposition. This is a low-pressure, low-temperature process used in an attempt to deposit diamond on substrates of glass, quartz, silicon, nickel, and boron nitride. Several deposition parameters have been varied including substrate temperature, gas concentration, gas pressure, total gas flow rate, rf input power, and deposition time. Analytical methods employed to determine composition and structure of the deposits include scanning electron microscopy, absorption spectroscopy, scanning Auger microprobe spectroscopy, and Raman spectroscopy. Analysis indicates that particles having a thin graphite surface, as well as diamond particles with no surface coatings, have been deposited. Deposits on quartz have exhibited optical bandgaps as high as 4.5 eV. Scanning electron microscopy analysis shows that particles are deposited on a pedestal which Auger spectroscopy
In recent years the nanocomposites of graphene oxide (GO) and different inorganic and organic compounds have shown great potential for charge storage applications. In present work we have investigated the influence of 12-tungstophosphoric acid (WPA) on surface chemistry of graphene oxide and thermal stability of nanocomposite. For this purpose nanocomposites with different mass ratios of GO and WPA were prepared. The thermal stability of nanocomposites was investigated by thermogravimetric and differential thermal analysis (TGA-DTA) while changes in surface chemistry of GO and structural properties of WPA were investigated by Fourier transform infrared spectroscopy (FTIR) and temperature programmed desorption (TPD) method. The TGA-DTA measurements of composites have shown that the major mass loss, due to carbon combustion, is shifted to higher temperatures (~500 °C vs. 380 °C of pure GO). Furthermore, when the amount of WPA is higher than 25 mass percent the nanocomposites start to act... like ...
An improved method and apparatus are disclosed for producing large area diamond depositions. A mixture of a carbon compound such as methane, hydrogen and argon is introduced into a DC arc plasma torch to form a plasma jet. The plasma jet is directed and trapped into a partially enclosed chemical vapor deposition zone confined within a reaction chamber of a CVD process. The chemical vapor deposition zone is formed by walls wherein at least one such wall is a rotating substrate cooled to a set temperature. The plasma jet containing radicalized hydrogen and a carbon compound is impinged on the rotating substrate to produce large area diamond layer.
TY - JOUR. T1 - TiO2 photoanodes with exposed {0 1 0} facets grown by aerosol-assisted chemical vapor deposition of a titanium oxo/alkoxy cluster. AU - Regue Grino, Miriam. AU - Sibby, Sandra. AU - Ahmet, Ibbi. AU - Friedrich, Dennis. AU - Abdi, Fatwa F.. AU - Johnson, Andrew. AU - Eslava Fernandez, Salvador. PY - 2019/8/28. Y1 - 2019/8/28. N2 - Photoelectrochemical water splitting is a promising technology for the development of solar fuels. Titanium dioxide (TiO 2) is one of the most studied metal oxides in this field as a photoanode. Achieving its full potential requires controlling its morphology and crystallinity and especially the exposure of its most active crystal facets. Herein, we present the formation of nanostructured TiO 2 photoanodes with anatase phase and high exposure of the {0 1 0} facet, the most active TiO 2 phase and facet. TiO 2 photoanodes were prepared from a Ti 7O 4(OEt) 20 titanium oxo/alkoxy cluster solution using aerosol assisted chemical vapor deposition. ...
Quantum capacitance of electrolyte-gated bilayer graphene field-effect transistors is investigated in this paper. Bilayer graphene has received huge attention due to the fact that an energy gap could be opened by chemical doping or by applying external perpendicular electric field. So, this extraordinary property can be exploited to use bilayer graphene as a channel in electrolyte-gated field-effect transistors. The quantum capacitance of bi-layer graphene with an equivalent circuit is presented, and also based on the analytical model a numerical solution is reported. We begin by modeling the DOS, followed by carrier concentration as a function |svg style=vertical-align:-0.20064pt;width:12.7375px; id=M1 height=11.375 version=1.1 viewBox=0 0 12.7375 11.375 width=12.7375 xmlns:xlink=http://www.w3.org/1999/xlink xmlns=http://www.w3.org/2000/svg||g transform=matrix(.017,-0,0,-.017,.062,11.112)||path id=x1D449 d=M730 650l-8 -28q-52 -4 -72 -18t-64 -77q-79 -113 -321 -539h-33l-119 541q-13
2017 Trans Tech Publications, Switzerland. Graphene oxide (GO) powder was synthesized by modified Hummers method. Bismuth vanadate (BiVO4) nanoparticle was synthesized by solvothermal method at 100 and 200°C for 3h. Composite graphene oxide and bismuth vanadate (GO/BiVO4) nanoparticle were synthesized by mixed oxide method in weight ratio of 0.20:1.00. The physical and chemical properties were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS) and surface area analyzer (BET). The photocatalytic degradation of methomyl performance was determined by high performance liquid chromatograph (HPLC). Composite GO/BiVO4 nanoparticle at 200°C for 3h was the highest photocatalytic degradation of methomyl ...
Determination of Pb (Lead), Cd (Cadmium), Cr (Chromium), Cu (Copper), and Ni (Nickel) in Chinese tea with high-resolution continuum source graphite furnace atomic absorption spectrometry ...
Optimization and validation of a methodology to determine total arsenic, As(III) and As(V), in water samples, through graphite furnace atomic absorption spectrometry ...
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0037] The base 218 can be identified/sequenced by the characteristics of the transistor current pulse triggered due to the presence of the base 218 inside the nanopore 110, such as, for example, the magnitude and the time duration of the transistor current pulse (the time it takes the DNA base to pass through the nanopore) as expected for the given base 218. When the base 218 is present inside the nanopore 110, the presence of this particular base 218 causes the transistor current to modulate (i.e., change). The transistor current flow (e.g., measured by the ammeter 220 when the base 218 is inside the nanopore 110) travels from the voltage source 219, through the metal layer 105a via hole 107, through one side of the graphene layer 104 to be modulated by the base 218 in the nanopore 110, to the other side (via the free-standing membrane 155) of the graphene layer 104, and out the metal layer 105b via the hole 108. FIG. 6 illustrates a graph 600 of the transistor current pulse measured by ammeter ...
EDITORIAL: King of the elements? King of the elements?. NASA Astrophysics Data System (ADS). Demming, Anna. 2010-07-01. sensitivity can be enhanced by two orders of magnitude when the graphene is doped with an impurity such as boron [11]. Work on graphene has also prompted the possibility of a new field of application in electron-spin-based quantum computing. In this issue, Patrik Recher and Björn Trauzettel in Germany present an overview on the latest research on quantum dots of graphene, graphene nanoribbons and discs in single- and bilayer graphene with a view to their possible application as qubits in computing [12]. Nanodiamonds with nitrogen vacancies have been shown to behave as quantum-dot-like fluorescent nanostructures that are not susceptible to bleaching. Once certain nanotoxicological concerns have been settled, such nanodiamonds may one day be useful for imaging, and means of industrial scale fabrication have already been reported [13]. Other possible medical applications of ...
Poster presentation: Monitoring the functionalization of single-walled carbon nanotubes with chitosan and folic acid by two-dimensional difusión-ordered NMR ...
TY - JOUR. T1 - Tin oxide meshes consisting of nanoribbons prepared through an intermediate phase in an aqueous solution. AU - Uchiyama, Hiroaki. AU - Imai, Hiroaki. PY - 2007/5/1. Y1 - 2007/5/1. N2 - Novel nanoarchitectures of SnO and SnO2 crystals that had two- and three-dimensionally meshed structures consisting of nanoribbons were prepared through Sn6U4(OH)4 as an intermediate state. Two-dimensional meshes consisting of oriented nanoribbons of single-crystalline tin monoxide (SnO) that was 50-300 nm wide were grown via Sn6O4(OH)4, which was initially produced at room temperature. Textured spherical particles with three-dimensional meshed nanostructures were produced at 60°C in the presence of citric acid in the aqueous system. The formation of the specific architectures is ascribed to the densely branching growth of SnO crystals in a matrix of Sn6O 4(OH)4 as a reactant. The meshed nanostructures of rutile-type tin dioxide were successfully obtained by oxidation of the SnO crystals without ...
2018 Electro-responsive materials were fabricated from poly(lactic) acid (PLA), incorporated with dibutyl phthalate (DBP) as a plasticizer and graphene nanoplatelet as an effective nanofiller, via solvent casting method. The electromechanical properties and deflection of MG/PLA/DBP composites were investigated under the effects of graphene concentration and electric field strength. All composites possessed good recoverability during the temporal response experiment under applied electric field. At the 0.1%v/v graphene, the composite exhibited the highest storage modulus sensitivity (ΔG′/G′0) value of 1.88 at the electric filed strength of 1.5 kV/mm. At the graphene concentration of 1.0%v/v, the storage modulus response (ΔG′) became negative definite, where the storage modulus under electric field (G′) was lower than the G′0value. The negative ΔG′ under electric field at room temperature has not been previously reported for any electrosrictive materials. Moreover, the pristine ...
United States Patent 3,462,289 PROCESS FOR PRODUCING REINFORCED CARBON AND GRAPHITE BODIES Cornelius W. Rohl, Lewiston, N.Y., and James H. Robinson, Canoga Park, Calif., assignors, by rnesne assignments, to The Carborunrlum Company, a corporation of Delaware No Drawing. Filed Aug. 5, 1965, Ser. No. 478,033 Int. Cl. C23c 9/06, 13/00; B44d N46 US. Cl. 11746 15 Claims ABSTRACT OF THE DISCLOSURE Carbon or graphite reinforced articles are produced by (l) forming reinforcing fibers into a shape, without any binder; (2) holding the shaped fibers under a vacuum; (3) pressure impregnating the fibers with carbonizable binder; (4) compressing the fibers to remove excess binder; (5) curing and (6) carbonizing the remaining binder; and (7) repeating at least once the vacuum, impregnation, curing and baking operations. The articles are substantially free of internal cracks and voids, therefore of high strength, even at relatively low densities. As such, the articles are particularly useful in the aerospace ...
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