Journal articles: 'Graphite lattice'

1

Sasaki, Naruo, Hideaki Okamoto, Shingen Masuda, Kouji Miura, and Noriaki Itamura. "Simulated Nanoscale Peeling Process of Monolayer Graphene Sheet: Effect of Edge Structure and Lifting Position." Journal of Nanomaterials 2010 (2010): 1–12. http://dx.doi.org/10.1155/2010/742127.

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The nanoscale peeling of the graphene sheet on the graphite surface is numerically studied by molecular mechanics simulation. For center-lifting case, the successive partial peelings of the graphene around the lifting center appear as discrete jumps in the force curve, which induce the arched deformation of the graphene sheet. For edge-lifting case, marked atomic-scale friction of the graphene sheet during the nanoscale peeling process is found. During the surface contact, the graphene sheet takes the atomic-scale sliding motion. The period of the peeling force curve during the surface contact decreases to the lattice period of the graphite. During the line contact, the graphene sheet also takes the stick-slip sliding motion. These findings indicate the possibility of not only the direct observation of the atomic-scale friction of the graphene sheet at the tip/surface interface but also the identification of the lattice orientation and the edge structure of the graphene sheet.

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Jiang, Yan Li, Mei Tian, Ying Hui Yu, Jia Yao Liu, and Shuang Liu. "Preparation and Property of Reduced Graphene for Hummers." Key Engineering Materials 591 (November 2013): 301–4. http://dx.doi.org/10.4028/www.scientific.net/kem.591.301.

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Graphene material has ideal lattice structure and unique electrical, optical and other properties. In the electronics, composite materials, and other fields it has a broad application prospect. In this paper, using the Hummers method, to prepare oxidized graphite and graphene , to optimize the conditions of the preparation of graphite oxide. With two kinds of reductors, glucose and hydrazine hydrate, reduction graphite oxide, and dropped silver ions in the process of reduction. Using XRD, SEM and Raman spectra to character and analyze the products. The result showed that the graphite and silver ions in the oxidation reaction process were both restored by glucose, hydrazine hydrate. This structure that silver nanoparticles are uniformly distributed in the graphene sheet layers, can effectively prevent the reunion of graphene layers, and also upset the rules of the pile of the graphene layers.

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Yürüm, Yuda, Burcu Saner Okan, Firuze Okyay, Alp Yürüm, Fatma Dinç, Neylan Görgülü, and Selmiye Alkan Gürsel. "An Improved Technique for the Exfoliation of Graphene Nanosheets and Utilization of their Nanocomposites as Fuel Cell Electrodes." Key Engineering Materials 543 (March 2013): 9–12. http://dx.doi.org/10.4028/www.scientific.net/kem.543.9.

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Graphene is a flat monolayer of carbon atoms tightly packed into a two-dimensional 2D honeycomb lattice. The graphene sheets in graphite interact with each other through van der Waals forces to form layered structure. The first graphene sheets were obtained by extracting monolayer sheets from the three-dimensional graphite using a technique called micromechanical cleavage in 2004 [. There are numerous attempts in the literature to produce monolayer graphene sheets by the treatment of graphite. The first work was conducted by Brodie in 1859 and GO was prepared by repeated treatment of Ceylon graphite with an oxidation mixture consisting of potassium chlorate and fuming nitric acid [. Then, in 1898, Staudenmaier produced graphite oxide (GO) by the oxidation of graphite in concentrated sulfuric acid and nitric acid with potassium chlorate [. However, this method was time consuming and hazardous. Hummers and Offeman found a rapid and safer method for the preparation of GO and in this method graphite was oxidized in water free mixture of sulfuric acid, sodium nitrate and potassium permanganate [.

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Burchell, T. D. "Radiation Effects in Graphite and Carbon-Based Materials." MRS Bulletin 22, no. 4 (April 1997): 29–35. http://dx.doi.org/10.1557/s0883769400033005.

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Displacement damage in graphite and carbon-based materials can occur when energetic particles, such as neutrons, ions, or electrons impinge on the crystal lattice. The displacement of carbon atoms from their equilibrium positions results in lattice strain, bulk dimensional change, and profound changes in physical properties. This article will discuss the effects of displacement damage in graphites and carbon-based materials. The materials considered here are those whose bonding is sp2—that is, graphites, pyrolytic carbons and graphites, carbon fibers, and carbon-carbon (C/C) composites. Radiation damage in sp3 (diamond) carbon forms is not discussed.Carbon-based materials and graphites are widely used in nuclear applications. For example, polygranular (manufactured) graphites have been employed as a moderator in nuclear reactors since the 1940s. More recently, pyrolytic graphites, artificial graphites, and C/C composites have been adopted as plasma-facing components in fusion devices. Engineering applications, such as those just cited, have necessitated a full understanding of the basic mechanisms of radiation damage, as well as the effects of radiation damage on the physical properties of carbon-based materials.

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5

Lei, Xiao-Wen, Shungo Shimizu, and Jin-Xing Shi. "The Theoretical Study of Kink Deformation in Graphite Based on Differential Geometric Method." Nanomaterials 12, no. 6 (March 9, 2022): 903. http://dx.doi.org/10.3390/nano12060903.

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Kink deformation is often observed in materials with laminated layers. Graphite composed of stacked graphene layers has the unique laminated structure of carbon nanomaterials. In this study, we performed the interlayer deformation of graphite under compression using a simulation of molecular dynamics and proposed a differential geometrical method to evaluate the kink deformation. We employed “mean curvature” for the representativeness of the geometrical properties to explore the mechanism of kink deformation and the mechanical behaviors of graphite in nanoscale. The effect of the number of graphene layers and the lattice chirality of each graphene layer on kink deformation and stress–strain diagrams of compressed graphite are discussed in detail. The results showed that kink deformation occurred in compressed graphite when the strain was approximately equal to 0.02, and the potential energy of the compressed graphite proportionately increased with the increasing compressive strain. The proposed differential geometric method can not only be applied to kink deformation in nanoscale graphite, but could also be extended to solving and predicting interlayer deformation that occurs in micro- and macro-scale material structures with laminated layers.

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KALONI, THANESWOR P., and SUGATA MUKHERJEE. "COMPARATIVE STUDY OF ELECTRONIC PROPERTIES OF GRAPHITE AND HEXAGONAL BORON NITRIDE (h-BN) USING PSEUDOPOTENTIAL PLANE WAVE METHOD." Modern Physics Letters B 25, no. 22 (August 30, 2011): 1855–66. http://dx.doi.org/10.1142/s0217984911027182.

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We studied various ground state properties, e.g. cohesive energy, exfoliation energy, equilibrium lattice constants, elastic constant (C33), compressibility, band structure, density of states and charge density of Graphite, Graphene and Hexagonal Boron Nitride (h- BN ) using pseudopotential plane wave method. Most of the calculated physical quantities of graphite are found to be close to those of h- BN and these are in good agreement with available experimental data.

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Manocha, L. M., Hasmukh Gajera, and S. Manocha. "Studies on synthesis and Reduction of Graphene Oxide from Natural Graphite by using Chemical Method." Eurasian Chemico-Technological Journal 13, no. 1-2 (December 21, 2010): 21. http://dx.doi.org/10.18321/ectj61.

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Graphene is a material with rapidly growing interest. It consists of flat monolayer of carbon atoms tightly packed into a two-dimensional (2D) honeycomb lattice and is basic building block for all graphitic materials. Interest in Graphene is because of its excellent mechanical, electrical, thermal, optical properties and its very high specific surface area. Studies have been performed on wet oxidation of natural graphite by using Modified Hummers Method followed by exfoliation and reduction in order to synthesise graphene from Graphite Oxide (GO). Acid route has been followed for oxidation whereas reduction has been carried out in water with hydrazine hydrate and Sodium Borohydrate. It results in to a material with characteristics that are comparable to those of pristine graphite. The reaction at every step has been characterized by using FTIR, TGA, XRD, Raman spectroscopy and surface area measurement.

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8

Endo, M., K. Oshida, K. Kobori, K. Takeuchi, K. Takahashi, and M. S. Dresselhaus. "Evidence for glide and rotation defects observed in well-ordered graphite fibers." Journal of Materials Research 10, no. 6 (June 1995): 1461–68. http://dx.doi.org/10.1557/jmr.1995.1461.

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New structural features observed in heat-treated vapor-grown carbon fibers (VGCF's), produced by the thermal decomposition of hydrocarbon vapor, are reported using image analysis of the lattice plane structure observed by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The TEM lattice image of well-ordered graphite fibers (heat-treated VGCF's at 2800 °C) was treated by a two-dimensional fast Fourier transform, showing sharp bright spots associated with the 002 and 100 lattice planes. The heat-treated VGCF's consist of a polygonally shaped shell, and the long and short fringe structures in the TEM lattice image reflect the 002 and 100 lattice planes, respectively. From this analysis, new facts about the lattice structure are obtained visually and quantitatively. The 002 lattice planes remain and are highly parallel to each other along the fiber axis, maintaining a uniform interlayer spacing of 3.36 Å. The 100 lattice planes are observed to make several inclined angles with the 002 lattice planes relative to the plane normals, caused by the gliding of adjacent graphene layers. This work visually demonstrates coexistence of the graphitic stacking, as well as the gliding of the adjacent graphene layers, with a gliding angle of about 3–20°. These glide planes are one of the dominant stacking defects in heat-treated VGCF's. On the other hand, turbostratic structural evidence was suggested by AFM observations. The structural model of coexisting graphitic, glide, and turbostratic structures is proposed as a transitional stage to perfect three-dimensional stacking in the graphitization process. These structural features could also occur in common carbons and in carbon nanotubes.

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9

Милахин, Д. С., Т. В. Малин, В. Г. Мансуров, Ю. Г. Галицын, А. С. Кожухов, И. А. Александров, Н. В. Ржеуцкий, Е. В. Лебедок, Е. А. Разумец, and К. С. Журавлев. "Формирование нанокристаллов GaN на поверхности графеноподобных g-AlN и g-Si-=SUB=-3-=/SUB=-N-=SUB=-3-=/SUB=-." Физика твердого тела 61, no. 12 (2019): 2327. http://dx.doi.org/10.21883/ftt.2019.12.48546.48ks.

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In this work, the GaN nanocrystals formation on a graphene-like modification of AlN (g-AlN) and graphene-like silicon nitride (g-Si3N3) by ammonia molecular beam epitaxy was studied. The GaN growth on the g-Si3N3 surface was found to result in the misoriented nanocrystals formation. With the GaN growth on the g-AlN surface, epitaxial growth of the equally oriented GaN quantum dots with graphite-like modification was observed. The lattice parameters and the energy structure of two GaN graphite-like modifications with alternating layers AB (graphite structure) and AA’ (hexagonal boron nitride structure) were calculated. This work was supported by the Russian Foundation for Basic Research (№ 17-02-00947-Бел_а and 18-52-00008-а). This work was supported by the Belarusian Republican Foundation for Basic Research in the framework of the joint project Ф18Р-234.

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10

Hüttinger, Klaus J. "The potential of The Graphite Lattice." Advanced Materials 2, no. 8 (August 1990): 349–55. http://dx.doi.org/10.1002/adma.19900020803.

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11

Nika, D. L., S. Ghosh, E. P. Pokatilov, and A. A. Balandin. "Lattice thermal conductivity of graphene flakes: Comparison with bulk graphite." Applied Physics Letters 94, no. 20 (May 18, 2009): 203103. http://dx.doi.org/10.1063/1.3136860.

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12

Abdulnabi, Hussein A., and Yasin Yousif Al-Aboosi. "Design of Tunable Multiband Hybrid Graphene Metal Antenna in Microwave Regime." Indonesian Journal of Electrical Engineering and Computer Science 12, no. 3 (December 1, 2018): 1003. http://dx.doi.org/10.11591/ijeecs.v12.i3.pp1003-1009.

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<p>Graphene is an <a title="Allotrope" href="https://en.wikipedia.org/wiki/Allotrope">allotrope</a> (form) of carbon consisting of a single layer of carbon atoms arranged in an <a title="Hexagonal lattice" href="https://en.wikipedia.org/wiki/Hexagonal_lattice">hexagonal lattice</a>. It is the basic structural element of many other allotropes of carbon, such as <a title="Graphite" href="https://en.wikipedia.org/wiki/Graphite">graphite</a>, <a title="Charcoal" href="https://en.wikipedia.org/wiki/Charcoal">charcoal</a>, <a title="Carbon nanotube" href="https://en.wikipedia.org/wiki/Carbon_nanotube">carbon nanotubes</a> and <a title="Fullerene" href="https://en.wikipedia.org/wiki/Fullerene">fullerenes</a>. In this paper, a tunable hybrid metal-graphene antenna in the microwave regime is proposed. This antenna composed of the copper patch and four graphene strips. The antenna designs used for the cellular long-term evolution system and the operating frequency bands of 1.8, 2.5, 2.6, and 3.6 GHz, are evaluated to demonstrate the working principle and the performance tradeoffs. Furthermore, the proposed antenna can be tuned by varying applied DC voltage on the graphene which leads to change in the chemical potential of the graphene and hence the surface conductivity and electrical properties are changed. The simulation results reveal that the antenna operates in multi-band where scattering factor S<sub>11</sub>< -10 dB. In addition, the results show that hybrid metal-graphene frequency reconfigurable antennas can, at the same time, provide a tunable bandwidth and antenna matching.</p>

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13

Söderlind, Per, Alexander Landa, Randolph Q. Hood, Emily E. Moore, Aurélien Perron, and Joseph T. McKeown. "High-Temperature Thermodynamics Modeling of Graphite." Applied Sciences 12, no. 15 (July 27, 2022): 7556. http://dx.doi.org/10.3390/app12157556.

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We present high-temperature thermodynamic properties for graphite from first-principles anharmonic theory. The ab initio electronic structure is obtained from density-functional theory coupled to a lattice dynamics method that is used to model anharmonic lattice vibrations. This combined approach produces free energies and specific heats for graphite that compare well with available experiments and results from models that empirically represent experimental data, such as CALPHAD. We show that anharmonic theory for the phonons is essential for accurate thermodynamic quantities above about 1000 K.

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Yang, Bo, and N. Vijayanand. "Multiscale Fracture in Peeling of Highly Oriented Pyrolytic Graphite." Key Engineering Materials 560 (July 2013): 71–86. http://dx.doi.org/10.4028/www.scientific.net/kem.560.71.

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Micromechanical cleavage is one of the methods used for isolation of single-and few-layer graphene sheets from bulk graphite. On the surface of peeled graphite flakes, nanosteps of precisely multiple-layer thickness are often observed. The nanosteps are believed to be termination edge of graphene sheets and formed by tearing graphene sheets sandwiched in the mouth of a main cleavage crack during the peeling process. In the present work, we introduce a continuum model to examine the peeling process that involves multiple fractures: the main cleavage fracture at the microscale, delamination of a graphene sheet from bulk graphite at the nanoscale, and tearing fracture of graphene at the atomistic scale. We apply von Karman's plate theory to model the graphene layer, the elastic fracture mechanics for the microscale cleavage crack, and a cohesive zone model for the nanoscale interlayer delamination and for the lattice-scale tearing fracture as well. With a reliable empirical interlayer potential, we could reveal the characteristic length scales involved in the multiscale fracture process. We show that the graphene layer is locally stretched to fracture in mode-I when von Karman's finite deflection effect in a plate is invoked, although the loading by the sandwiching cleavage crack faces is nominally tearing in mode-III.

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15

Bross, Helmut. "From Graphite to Graphene: The Confinement of the Fermi Surface to the Line KH." ISRN Condensed Matter Physics 2013 (May 7, 2013): 1–9. http://dx.doi.org/10.1155/2013/327913.

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The graphite structure is self-consistently calculated by use of the all electron Modified Augmented Plane Wave (MAPW) scheme with lattice constants considerably enlarged above the experimental value of graphite. Overall, the band structures of the series are found to be quite similar: the energy levels of the highly symmetric states K and H almost coincide, essentially fixing the Fermi level of the semimetallic solid. The dispersion along lines parallel to the atomic planes, already small in graphite at the experimental value of , continues to flatten with increasing value of . The structure with an interlayer distance enlarged by the factor 3 over the experimental value provides a good approximation of the behaviour of a monoatomic sheet. In this context, the unusual behaviour of graphene appears in a new light.

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Grushevski, E., D. Savelev, L. Mazaletski, N. Savinski, and D. Puhov. "The scalable production of high-quality nanographite by organic radical-assisted electrochemical exfoliation." Journal of Physics: Conference Series 2086, no. 1 (December 1, 2021): 012014. http://dx.doi.org/10.1088/1742-6596/2086/1/012014.

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Abstract One of the promising ways to produce graphene is the technology of graphite splitting or exfoliation, both by physical or mechanical and chemical, including electrochemical methods. The product of electro exfoliation is nanographite, which is transformed into multigraphene at the subsequent stage of liquid-phase mechanical and ultrasonic disintegration. This approach demonstrates a successful method of obtaining multigraphene from available graphite raw materials. Since, already at a potential of 1.23V, during the electrolysis of water on a graphite anode, the hydroxyl anion is discharged with the formation of a very active hydroxyl radical oxidizer, it is not surprising that when the graphite electro exfoliation process is overvolted at 10V, graphite oxidation products are formed. In order to control the defectiveness of the graphene lattice by oxidation products, we carried out processes of graphite exfoliation in the presence of both a number of reducing agents ascorbic acid, sodium borohydride, hydrazine hydrate, and in the presence of industrial antioxidants radical traps (2,2,6,6-tetramethylpiperidine-1-il)oxyl (TEMPO), (2,2,6,6-tetramethyl-4 oxo-piperidine-1-yl)oxyl (IPON), a mixture of 5,8,9-bis isomers[(2,2,6,6-tetramethyl - 4 oxo-piperidine-1-yl)]-{5,8,9-[1,1’- bi(cyclopentylidene)]-2,2’,4,4’- tetraene}(YARSIM-0215). It should be noted, that the best result of preventing the oxidation of nanographite in electro exfoliation technology in our studies is the ratio of carbon to oxygen (C/O) about 69.

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Spitzer, Saskia, Oliver Helmle, Oliver Ochs, Joshua Horsley, Natalia Martsinovich, Wolfgang M. Heckl, and Markus Lackinger. "What can be inferred from moiré patterns? A case study of trimesic acid monolayers on graphite." Faraday Discussions 204 (2017): 331–48. http://dx.doi.org/10.1039/c7fd00113d.

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Self-assembly of benzene-1,3,5-tricarboxylic acid (trimesic acid – TMA) monolayers at the alkanoic acid–graphite interface is revisited. Even though this archetypal model system for hydrogen bonded porous networks is particularly well studied, the analysis of routinely observed superperiodic contrast modulations known as moiré patterns lags significantly behind. Fundamental questions remain unanswered such as, are moiré periodicity and orientation always the same, i.e. is exclusively only one specific moiré pattern observed? What are the geometric relationships (superstructure matrices) between moiré, TMA, and graphite lattices? What affects the moiré pattern formation? Is there any influence from solvent, concentration, or thermal treatment? These basic questions are addressed via scanning tunneling microscopy experiments at the liquid–solid interface, revealing a variety of different moiré patterns. Interestingly, TMA and graphite lattices were always found to be ∼5° rotated with respect to each other. Consequently, the observed variation in the moiré patterns is attributed to minute deviations (<2°) from this preferred orientation. Quantitative analysis of moiré periods and orientations facilitates the determination of the TMA lattice parameter with picometer precision.

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Zhang, Ling, Ling Li, Zong Gang Mou, and Xi Feng Li. "Preparation and Characterization of BCN–TiO₂ Nanoparticles." Advanced Materials Research 306-307 (August 2011): 1375–78. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.1375.

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BCN–TiO2 was prepared by doping Ti(OH)4 with graphite-like structure BCN in an annealing process at 400[°C] for 2[h]. The catalyst samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). Graphite-like structure BCN was detected by XRD. The results showed that with graphite-like structure BCN doped in, the crystal size became smaller than pure TiO2. Also B, C, N were detected in crystal lattice of TiO2, in which Boron was in the form of Bx+, Carbon substituted some of the lattice oxygen atoms as Ti-C, and Nitrogen was in the form of Ti-N and Ti-O-N.

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Gupta, H. C., Jaishree Malhotra, N. Rani, and B. B. Tripathi. "Lattice dynamics of alkali graphite intercalation compounds." Synthetic Metals 34, no. 1-3 (December 1989): 347–52. http://dx.doi.org/10.1016/0379-6779(89)90407-4.

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20

SCHLOEGL, R. "ChemInform Abstract: Graphite - A Unique Host Lattice." ChemInform 26, no. 34 (August 17, 2010): no. http://dx.doi.org/10.1002/chin.199534275.

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Qu, Hua, and Wei Dong Liu. "Analysis of Structural Condition and Thermodynamics Condition of Graphite Heterogeneity Nucleation in Cast Iron." Advanced Materials Research 299-300 (July 2011): 576–79. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.576.

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Based on the empirical electron theory of solid and molecule, the valence electron structures(VESs) of graphite, CaS and MnS in cast iron are calculated, their bond-forming energy F of the structure unit and bond-forming energyEof the crystal plane are defined and calculated. Combined with the nucleation theory of the liquid metal,Fand E are applied to analyze the thermodynamics condition of graphite heterogeneity nucleation in undercooling liquid of case iron, i.e.,GL-FG>GL-FH,>. According to the coincidence lattice model of large-angle grain boundary used commonly in modern times, the corresponding structural condition is analyzed, i.e., the crystal structure of graphite should have the better lattice contract ratio with the crystal structure of its annexed heterogeneous particles.

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Kapcia, Konrad Jerzy. "Charge-Order on the Triangular Lattice: A Mean-Field Study for the Lattice S = 1/2 Fermionic Gas." Nanomaterials 11, no. 5 (April 30, 2021): 1181. http://dx.doi.org/10.3390/nano11051181.

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The adsorbed atoms exhibit tendency to occupy a triangular lattice formed by periodic potential of the underlying crystal surface. Such a lattice is formed by, e.g., a single layer of graphane or the graphite surfaces as well as (111) surface of face-cubic center crystals. In the present work, an extension of the lattice gas model to S=1/2 fermionic particles on the two-dimensional triangular (hexagonal) lattice is analyzed. In such a model, each lattice site can be occupied not by only one particle, but by two particles, which interact with each other by onsite U and intersite W1 and W2 (nearest and next-nearest-neighbor, respectively) density-density interaction. The investigated hamiltonian has a form of the extended Hubbard model in the atomic limit (i.e., the zero-bandwidth limit). In the analysis of the phase diagrams and thermodynamic properties of this model with repulsive W1>0, the variational approach is used, which treats the onsite interaction term exactly and the intersite interactions within the mean-field approximation. The ground state (T=0) diagram for W2≤0 as well as finite temperature (T>0) phase diagrams for W2=0 are presented. Two different types of charge order within 3×3 unit cell can occur. At T=0, for W2=0 phase separated states are degenerated with homogeneous phases (but T>0 removes this degeneration), whereas attractive W2<0 stabilizes phase separation at incommensurate fillings. For U/W1<0 and U/W1>1/2 only the phase with two different concentrations occurs (together with two different phase separated states occurring), whereas for small repulsive 0<U/W1<1/2 the other ordered phase also appears (with tree different concentrations in sublattices). The qualitative differences with the model considered on hypercubic lattices are also discussed.

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Asthana, Anjana, Yoshio Matsui, Makoto Yasuda, Koji Kimoto, Tadao Iwata, and Ken-ichi Ohshima. "Investigations on the structural disordering of neutron-irradiated highly oriented pyrolytic graphite by X-ray diffraction and electron microscopy." Journal of Applied Crystallography 38, no. 2 (March 11, 2005): 361–67. http://dx.doi.org/10.1107/s0021889805004292.

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Light and heavy neutron-irradiation damage of highly oriented pyrolytic graphite (HOPG) crystals was examined by means of X-ray diffraction and high-resolution high-voltage transmission electron microscopy (TEM). From the X-ray data analysis, it was found that there is an average increase of about 3% in thec-axis lattice parameter of the unit cell of graphite for lightly neutron-irradiated HOPG. However, thec-axis lattice parameter could not be estimated from the HOPG sample having the highest dose of neutron irradiation under the present investigation, because the X-ray profile was highly asymmetrical. This increase in thec-axis lattice parameter is attributed to lattice expansion due to the static displacement of atoms after neutron irradiation. Local structure analysis by TEM shows that the 0002 lattice spacing for the above-mentioned HOPG samples has been increased by up to 10% as a result of the neutron irradiation. This increase inc-axis lattice spacing can be ascribed to the fragmentation of the crystal lattice into nanocrystallites, breaking and bending of the 0002 straight lattice fringes, appearance of dislocation loops, and extra interstitial planes within the fragmented nanocrystallites. All these changes are a result of the static displacement of atoms after neutron irradiation.

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Lueking, Angela D., Ling Pan, Deepa L. Narayanan, and Caroline E. B. Clifford. "Effect of Expanded Graphite Lattice in Exfoliated Graphite Nanofibers on Hydrogen Storage." Journal of Physical Chemistry B 109, no. 26 (July 2005): 12710–17. http://dx.doi.org/10.1021/jp0512199.

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Lardizábal-G., Daniel, I. L. Alonso-Lemus, L. de la Torre Saenz, A. Aguilar-Elguezabal, and Ysmael Verde-Gómez. "Short-route synthesis method of N-doped exfoliated graphite whit catalytic activity for the oxygen reduction reaction." MRS Advances 5, no. 57-58 (2020): 2939–46. http://dx.doi.org/10.1557/adv.2020.381.

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AbstractWe report the synthesis of metal-free nitrogen-doped electrocatalysts obtained from graphite and urea as carbon and nitrogen precursor, respectively. High-energy milling and thermal annealing were carried out to obtain low cost electrocatalysts. Additionally, this method has shorter synthesis times, is environmentally friendly and use high-availability raw materials. A short-route synthesis consisted in the partial exfoliation of graphite by mechanical milling with urea. Afterwards, nitrogen was integrated into the exfoliated graphite lattice by thermal annealing at 500°C. XPS analyses shows up to 1.7 at. % was incorporated to the graphitic lattice. Scanning Electron Microscopy, X-ray diffraction and Raman Spectroscopy were used to analyse the morphology and structural features. The catalytic activity for the oxygen reduction reaction in basic media was evaluated by the rotating disk electrode technique.

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Morrison, Craig N., Andrey P. Jivkov, Gillian Smith, and John R. Yates. "Lattice-Spring Modeling of Graphite Accounting for Pore Size Distribution." Key Engineering Materials 592-593 (November 2013): 92–95. http://dx.doi.org/10.4028/www.scientific.net/kem.592-593.92.

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Lattice models allow length scale dependent micro-structural features and damage mechanisms to be incorporated into analyses of mechanical behaviour. They are particularly suitable for modelling the fracture of nuclear graphite, where porosity generates local failures upon mechanical and thermal loading. Our recent 3D site-bond model is extended here by representing bonds with spring groups. Experimentally measured distributions of pore sizes in graphite are used to generate models with pores assigned to the bonds. Microscopic damage is represented by failure of normal and shear springs with different criteria based on force and pore size. Macroscopic damage is analysed for several loading cases. It is shown that, apart from uniaxial loading, the development of micro-failures yields damage-induced anisotropy in the material. This needs to be accounted for in constitutive laws for graphite behaviour in FEA of cracked reactor structures.

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Blanton, Thomas N., and Debasis Majumdar. "X-ray diffraction characterization of polymer intercalated graphite oxide." Powder Diffraction 27, no. 2 (June 2012): 104–7. http://dx.doi.org/10.1017/s0885715612000292.

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Graphite oxide (GO) is generated by treating graphite with strong oxidizers. GO retains the structure of graphite, but does so with a larger and irregular basal plane spacing. The oxidation of graphite results in the formation of epoxide groups, as well as C–OH and COOH groups. It is the presence of some of these moieties that allows GO to be dispersed in water, allowing for its use in waterborne formulations. Although GO does not possess the electrical properties of single-sheet graphene, it can be swelled in water, which allows for intercalation of hydrophilic polymer between GO sheets, resulting in a composite that can be coated to produce a continuous film. After coating it may be possible to chemically convert GO to a reduced graphite oxide (r-GO) with improved electrical conductivity. X-ray diffraction (XRD) is ideally suited to evaluate GO–polymer composite samples for evidence of intercalation or exfoliation of GO. Examples of GO–polymer analysis by XRD are presented, along with results that demonstrate the effect of relative humidity (RH) on neat GO. Knowing the ambient RH during XRD data collection was found to be important to correctly assess the extent of polymer intercalation within the GO lattice.

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Van Ngo, Vinh, Mike Hernandez, Bill Roth, and David C. Joy. "STEM Imaging of Lattice Fringes and beyond in a UHR In-Lens Field-Emission SEM." Microscopy Today 15, no. 2 (March 2007): 12–17. http://dx.doi.org/10.1017/s1551929500050951.

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The phase-contrast imaging of atomic lattices has now become commonplace for both Transmission Electron Microscopes (TEM) and Scanning Transmission Electron Microscopes (STEMs). Recently, however, bright-field STEM images of multi-wall carbon nanotubes (MWCNTs) recorded from an ultra-high resolution (UHR) in-lens field-emission scanning electron microscope (FE-SEM) operating at 30keV have also demonstrated lattice fringe resolution. One example of such an image containing multiple examples of fringe detail is shown in figure 1. The carbon lattice fringes were analyzed and their origin confirmed by the application of the FFT algorithms in the SMART image analysis program. The resulting power spectrum after thresholding to remove background noise (Figure 2) confirms that phase detail in the image extends down to about 5 Angstroms (0.5nm) and that well defined diffraction spots corresponding to a spacing of 3.4 Angstroms (0.34nm) generated by the (002) basal plane spacing of the graphite lattice are present.

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29

Sur, Ujjal Kumar. "Graphene: A Rising Star on the Horizon of Materials Science." International Journal of Electrochemistry 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/237689.

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Graphene, a one-atom thick planar sheet of sp2bonded carbon atoms packed in a honeycomb lattice, is considered to be the mother of all graphitic materials like fullerenes, carbon nanotubes, and graphite. Graphene has created tremendous interest to both physicists and chemists due to its various fascinating properties, both observed and predicted with possible potential applications in nanoelectronics, supercapacitors, solar cells, batteries, flexible displays, hydrogen storage, and sensors. In this paper, a brief overview on various aspects of graphene such as synthesis, functionalization, self-assembly, and some of its amazing properties along with its various applications ranging from sensors to energy storage devices had been illustrated.

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30

Taufantri, Yudha, Irdhawati Irdhawati, and Ida Ayu Raka Astiti Asih. "Sintesis dan Karakterisasi Grafena dengan Metode Reduksi Grafit Oksida Menggunakan Pereduksi Zn." Jurnal Kimia VALENSI 2, no. 1 (May 31, 2016): 17–23. http://dx.doi.org/10.15408/jkv.v2i1.2233.

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Graphene is a thin material, has a hexagonal two-dimentional lattice and is considered as an interesting material for adsorption process. Nowadays, graphene has been known as a potential material for diverse application, such as adsorbent. In this study graphene was synthesized from graphite. Furthermore, graphene was applied for adsorption of dichloro diphenyl trichloroethane (DDT). Graphene was synthesized by Hummer’s method using hydrothermal and reduced by Zn. The samples were characterized by Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) methods. The results of the XRD showed graphene structure in the 2θ, appeared at 23.9369 with interlayer spacing was about 3.71763 Å, compared with graphite oxide structure in the 2θ appeared at 11.2055 with interlayer spacing was about 7.89649 Å. The results of SEM analysis showed graphene has one layer with planar hexagonal structure and seems transparent whose single layer and multi layers. The graphene adsorption was analyzed by using the UV-Visible spectrophotometer. The results indicated the surface area of graphene was shown as 46.8563 m2/g. The amount of DDT adsorbed by graphene during 15 minutes was 7.5859 mg/g. This adsorption mechanism of DDT and graphene might be due to π-π and hydrogen interactions. Keywords: Adsorption, dichloro diphenyl trichloroethane (DDT), graphena. DOI: http://dx.doi.org/10.15408/jkv.v2i1.2233

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31

Kitajima, Masahiro, Eiji Asari, and Kazutaka G. Nakamura. "Lattice Disordering and Its Thermal Relaxation of Graphite." TANSO 1995, no. 166 (1995): 47–54. http://dx.doi.org/10.7209/tanso.1995.47.

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32

Okuyama, Fumio, Tatsuji Hayashi, and Yasutaka Fujimoto. "Graphite lattice synthesis catalyzed by chromium-containing crystallites." Applied Physics Letters 74, no. 24 (June 14, 1999): 3726–28. http://dx.doi.org/10.1063/1.123234.

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33

Hishiyama, Yoshihiro, and Michio Inagaki. "Lattice parameter changes in graphite with boron doping." Carbon 39, no. 1 (January 2001): 150–52. http://dx.doi.org/10.1016/s0008-6223(00)00207-4.

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34

Krupska, A., W. Jurga, L. Piekara-Sady, P. Szroeder, and F. Rozpłoch. "Effect of lattice compression on -factor in graphite." Solid State Communications 148, no. 3-4 (October 2008): 148–50. http://dx.doi.org/10.1016/j.ssc.2008.07.035.

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35

Lauter, H. J., V. L. P. Frank, H. Taub, and P. Leiderer. "Lattice dynamics of commensurate monolayers adsorbed on graphite." Physica B: Condensed Matter 165-166 (August 1990): 611–12. http://dx.doi.org/10.1016/s0921-4526(90)81155-h.

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36

Rettig, C., M. B decker, and H. H vel. "Carbon-nanotubes on graphite: alignment of lattice structure." Journal of Physics D: Applied Physics 36, no. 7 (March 19, 2003): 818–22. http://dx.doi.org/10.1088/0022-3727/36/7/308.

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37

Jialin, Zhang, Liu Yiyang, Lu Shanfu, and Xiang Yan. "Nitrogen, Phosphorus Co-Doped Graphite Felt as Highly Efficient Electrode for VO2+/VO2+ Reaction." Batteries 9, no. 1 (January 5, 2023): 40. http://dx.doi.org/10.3390/batteries9010040.

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All-vanadium redox flow batteries hold promise for the next-generation grid-level energy storage technology in the future. However, the low electrocatalytic activity of initial graphite felt constrains the development of VRFBs. Furthermore, the positive VO2+/VO2+ reaction involves complex multistep processes and more sluggish kinetics than negative V2+/V3+ reaction. Therefore, enhancing the kinetics of positive reaction is especially important. Heteroatom doping is one of the effective strategies for preparing carbon electrodes with high electrocatalytic activity and good stability. Here, a nitrogen, phosphorus co-doped graphite felt is prepared. Nitrogen introduces more negative charge into the carbon lattice due to the higher electronegativity, and more oxygen-containing functional groups will be introduced into the carbon lattice due to phosphorus-doped graphite felt. N, P co-doping provides more adsorption sites for vanadium ions. As a result, nitrogen, phosphorus co-doped graphite felt shows high electrochemical activity and good stability, and the corresponding VRFB presents a good voltage efficiency of 75% at a current density of 300 mA cm−2, which is 11% higher than the pristine graphite felt. During 100 charge/discharge cycles, the energy efficiency and voltage efficiency remain at 84% and 86% under the current density of 150 mA cm−2.

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AGOSTINO, A., E. BONOMETTI, P. VOLPE, M. TRUCCATO, C. MANFREDOTTI, P. OLIVERO, C. PAOLINI, G. RINAUDO, and L. GOZZELINO. "CARBON INFLUENCE IN THE SYNTHESIS OF MgB2 BY A MICROWAVE METHOD." International Journal of Modern Physics B 17, no. 04n06 (March 10, 2003): 773–78. http://dx.doi.org/10.1142/s0217979203016595.

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We describe a method to produce MgB 2 bulk via a microwave processing, which has not been reported yet for this material. We used two experimental arrangements, which were different in the form of the graphite thermal activator responsible for the microwave absorption. The reaction products have been analyzed from the morphological, structural and electronic point of view. The results show that the critical temperature is decreased by about 4 K when the graphite can diffuse inside the reaction cell and is incorporated in the samples, even if no evidence of carbon substitution in the MgB 2 lattice is given by the lattice constants. We point out that excellent conductivity features are achieved for nearly carbon-free samples.

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39

Ponsurya, P., Shahid Hussain, B. H. Abbas Shahul Hameed, R. Perumalsamy, R. Thirumamagal, M. Jayachandran, and A. Ayeshamariam. "Studies on Growth Mechanism of Annealed Graphite Powder and Gas-Sensor Applications." Materials Science Forum 832 (November 2015): 102–9. http://dx.doi.org/10.4028/www.scientific.net/msf.832.102.

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High quality micro sheet rhombohedral graphite crystals were synthesized by Hummer method using compounds of MWCNT, K2S2O8and P2O5. The growth mechanisms were discussed by finite element simulation. The synthetic sheet rhombohedral graphite crystals showed a higher growth rate in radial direction than that in axial direction. Raman spectrum and Fourier transform infrared spectrum indicated that synthesized sheet rhombohedral Graphite had fewer crystal lattice distortions with no impurities. Finite element simulations indicated that the solvent metal convection field in the radial direction was stronger than that in the axial direction. As prepared graphite powder was annealed at 1350 oC to obtain diamond nanoparticles. The as-prepared products were exposed to formaldehyde gas.

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40

Rahmawati, Fitria, Sayekti Wahyuningsih, and Nurani Handayani. "SURFACE MODIFICATION OF SEMICONDUCTOR THIN FILM OF TiO₂ ON GRAPHITE SUBSTRATE BY Cu-ELECTRODEPOSITION." Indonesian Journal of Chemistry 8, no. 3 (June 17, 2010): 331–36. http://dx.doi.org/10.22146/ijc.21587.

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Surface modification of graphite/TiO2 has been done by mean of Cu electrodeposition. This research aims to study the effect of Cu electrodeposition on photocatalytic enhancing of TiO2. Electrodeposition has been done using CuSO4 0,4 M as the electrolyte at controlled current. The XRD pattern of modified TiO2 thin film on graphite substrate exhibited new peaks at 2θ= 43-44o and 2θ= 50-51o that have been identified as Cu with crystal cubic system, face-centered crystal lattice and crystallite size of 26-30 nm. CTABr still remains in the material as impurities. Meanwhile, based on morphological analysis, Cu particles are dissipated in the pore of thin film. Graphite/TiO2/Cu has higher photoconversion efficiency than graphite/TiO2. Keywords: semiconductor, graphite/TiO2, Cu electrodeposition

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41

Stöwe, Klaus. "Zur Struktur und Dotierung von Selenosilikaten: die Kristallstruktur von Er2SeSiO4 und Er3,75Ca0,25Se2,75Cl0,25Si2O7 Structure and Doping of Seleno Silicates: the Crystal Structures of Er2SeSiO4 and Er3,75Ca0,25Se2,75Cl0,25Si2O7." Zeitschrift für Naturforschung B 49, no. 6 (June 1, 1994): 733–40. http://dx.doi.org/10.1515/znb-1994-0603.

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Well-shaped brown and pink isometric crystals were obtained as by-products of the synthesis of erbium selenides from the elements in evacuated and sealed silica ampoules with graphite inlets. They could be identified as erbium seleno mono- and disilicates by energy dispersive X-ray fluorescence and X-ray structure determination. The monosilicate Er2SeSiO4 crystallizes isotypically to Nd2SeSiO4 in the space group Pbcm with the lattice parameters a = 600.2(2), b = 688.0(2), c = 1075.2(2) pm and represents the second known seleno inosilicate of the rare earths. From X-ray structure analysis an isotypic relation between the disilicate Er3,75Ca0,25Se2,75Cl0,25Si2O7 and the compound Sm4S3Si2O7 was found, the former crystallizing in the space group I41/amd with the lattice parameters a - 1177.7(2) and c = 1376.5(2) pm. The doping o f the sorosilicate with the elements Ca and Cl originated from contam inations in the graphit inlets used in the procedure

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42

Qi, Ming-Bo, Peng-Fei Lian, Peng-Da Li, He-Yao Zhang, Jin-Xing Cheng, Qing-Bo Wang, Zhong-Feng Tang, T. J. Pan, Jin-Liang Song, and Zhan-Jun Liu. "Diffusion Behavior of Iodine in the Micro/Nano-Porous Graphite for Nuclear Reactor at High Temperature." C 9, no. 3 (August 26, 2023): 81. http://dx.doi.org/10.3390/c9030081.

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The diffusion behavior of iodine in micro/nano-porous graphite under high-temperature conditions was studied using analysis methods such as Rutherford backscattering Spectrometry, scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. The results indicate that iodine diffusion leads to the Lattice Contractions in Microcrystals, a decrease in interlayer spacing, and a rise of defect density. And the reversal or repair of microstructure change was observed: the microcrystal size of the graphite increases, the interlayer spacing appears to return to the initial state, and the defect density decreases, upon diffusion of iodine out of iodine-loaded graphite. The comparative study comparing the iodine diffusion performance of nanoporous graphite (G400 and G450) between microporous graphite (G500), showed that nanoporous graphite exhibits a better barrier to the iodine diffusion. The study on the diffusion behavior of iodine in micro/nano-porous graphite holds substantial academic and engineering value for the screening, design, and performance optimization of nuclear graphite.

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Sinitsyna, Olga V., Georgy B. Meshkov, Anastasija V. Grigorieva, Alexander A. Antonov, Inna G. Grigorieva, and Igor V. Yaminsky. "Blister formation during graphite surface oxidation by Hummers’ method." Beilstein Journal of Nanotechnology 9 (February 2, 2018): 407–14. http://dx.doi.org/10.3762/bjnano.9.40.

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Graphite oxide has a complex structure that can be modified in many ways to obtain materials for a wide range of applications. It is known that the graphite precursor has an important role in the synthesis of graphite oxide. In the present study, the basal-plane surface of highly annealed pyrolythic graphite (HAPG) was oxidized by Hummers’ method and investigated by Raman spectroscopy and atomic force microscopy. HAPG was used as a graphite precursor because its surface after cleavage contains well-ordered millimeter-sized regions. The treatment resulted in graphite intercalation by sulfuric acid and blister formation all over the surface. Surprisingly, the destruction of the sp2-lattice was not detected in the ordered regions. We suggest that the reagent diffusion under the basal plane surface occurred through the cleavage steps and dislocations with the Burgers vector parallel to the c-axis in graphite.

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44

Zhao, Hao Jiang, Rong Qiang Liu, and Hong Wei Guo. "Effects of Material Parameters on Longitudinal Vibration Band Gaps in Thin Phononic Crystal Plates." Applied Mechanics and Materials 654 (October 2014): 16–19. http://dx.doi.org/10.4028/www.scientific.net/amm.654.16.

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The improved plane wave expansion method is used to investigate the effects of material parameters on the longitudinal vibration band gaps in thin phononic crystal plates. Both square lattice and graphite lattice are considered. Results show that the parameters playing the essential roles are the mass density ratio and the Young modulus ratio of the scatterers and the host materials.

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45

Li, Li, and Shi Bo Xing. "Calculation Method of the Lattice Constants of Crystal at Different Temperature and Pressure." Advanced Materials Research 850-851 (December 2013): 20–23. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.20.

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The lattice constants of crystal are the basis of the valence electron structure calculation with the bond length difference method of the empirical electron theory of the solid and molecules. However, the lattice constants change with temperature and pressure. In this paper, according to the nature of thermal expansion of crystal and generalized Hookes law, the relationships among lattice constants, temperature and pressure are established by using linear thermal expansion coefficient and elastic constant. Taken the lattice constants of hexagonal graphite as an example, the calculation results agree with experimental data greatly, which prove the viability of this calculation method.

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46

Bespala, Evgeny V., Alexander O. Pavliuk, Vladimir S. Zagumennov, and Sergey G. Kotlyarevskiy. "About chemical form and binding energy of 14C in irradiated graphite of uranium-graphite nuclear reactors." Nuclear Energy and Technology 4, no. 1 (October 17, 2018): 51–56. http://dx.doi.org/10.3897/nucet.4.29855.

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Issues associated with handling irradiated graphite of uranium-graphite nuclear reactors are examined. It is demonstrated that selection of approaches, methods and means for handling irradiated graphite are determined by the form of occurrence and binding energy of long-lived 14C radionuclide with graphite crystalline lattice. The purpose of the present study is the determination of possible chemical compounds in which 14C can be found and assessment of fastness of its binding in the structure of irradiated graphite. Indigent and foreign experience of handling graphite radioactive wastes was analyzed, calculations and measurements were performed. Information was provided on the channels of accumulation of 14C in the structure of reactor graphite and it was demonstrated that the largest quantities of the radionuclide in question are generated according to the reaction 14N(n, p)14C. Here, most part of radioactive carbon is generated on 14N nuclei found in the form of impurities in non-irradiated graphite and in the composition of gas used for purging nuclear reactor in the process of operation. 14C radionuclide generated according to 14N(n, p)14C nuclear reaction is localized in the near subsurface graphite layer (in the near subsurface layer of pores) at the depth of not more than 50 nm. Analysis was performed of possible chemical compounds which may incorporate radioactive carbon. It was established that the form of occurrence is determined by the operational properties of specific graphite element in the reactor core. 14C binding energy in the structure of irradiated graphite was evaluated and depth of its penetration in the structure was calculated. It was established that selective extraction of this radionuclide is possible only under elevated temperatures in weakly oxidizing environment which is explained by the binding energy reaching up to 800 kJ/mole in the process of chemical sorption of 14C on the surface of graphite and depth of its occurrence equal to ~ 70 nm in the course of ion implantation. It was demonstrated that radioactive carbon generated according to 13C(n, γ)14C nuclear reaction is uniformly distributed among graphite elements and possesses binding energy ~477 kJ/mole. Its selective extraction is possible only under the condition of destruction of graphite crystalline lattice and organization of the process of isotopic separation. The obtained results allow recommending the most efficient methods of handling irradiated graphite during decommissioning uranium-graphite reactors.

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47

Pan, Xiaoyan. "Study on preparation and properties of nanocrystalline TiO₂/graphite photocatalytic composite by mechanochemistry." Journal of Physics: Conference Series 2539, no. 1 (July 1, 2023): 012057. http://dx.doi.org/10.1088/1742-6596/2539/1/012057.

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Abstract Graphite-modified TiO2 composite is a promising photocatalyst in environmental purification. In this study, TiO2/graphite photocatalytic composites were prepared by mechanochemistry using natural flake graphite and nanocrystalline TiO2 as raw materials. The composites were examined by X-ray diffractometer, Raman spectrometer, X-ray photoelectron spectrometer, scanning electron microscope and UV-vis spectrophotometer. The photoelectrochemical properties of the composites were investigated via electrochemical impedance spectroscopy and photocurrent response. The influences of the content and premilling time of graphite on the photocatalytic properties of the composites were studied through the photocatalytic decomposition of methylene blue. The results showed that graphite was exfoliated and broken during ball milling, and defects of graphite increased with the extension of milling time. In the composite, there is no solid solution of carbon atoms in TiO2 lattice. The photocatalytic results indicated that a proper amount of graphite could improve the photocatalytic behavior of TiO2. The TiO2/graphite composite containing 1wt% graphite exhibited the best photocatalytic behavior. The pretreatment of graphite by ball milling could enhance the photocatalytic behavior of the TiO2/graphite composite and the optimal premilling time of graphite was 4 hours.

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48

Enoki, Toshiaki, Seiichi Miyajima, Mizuka Sano, and Hiroo Inokuchi. "Hydrogen-alkali-metal-graphite ternary intercalation compounds." Journal of Materials Research 5, no. 2 (February 1990): 435–66. http://dx.doi.org/10.1557/jmr.1990.0435.

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Alkali-metal-graphite intercalation compounds (alkali-metal-GIC's) absorb hydrogen in two ways: physisorption and chemisorption. Hydrogen uptake through the physisorption process occurs at low temperatures below about 200 K in higher stage alkali-metal-GIC's, where hydrogen molecules are stabilized to form a two-dimensional condensed phase in the galleries of the graphite sheets. The concentration of absorbed hydrogen molecules is saturated at a rate of H2/alkali metal atom ∼2. The hydrogen physisorption shows a strong isotope effect and a swelling effect on c-axis lattice expansion. In the case of hydrogen uptake through the chemisorption process, dissociated hydrogen species are stabilized in the intercalate spaces. The activity of the chemisorption increases in the order Cs < Rb < K. The introduction of hydrogen generates a charge transfer from the host alkali metal GIC's to the hydrogen since hydrogen has strong electron affinity. The hydrogenated potassium-GIC's have intercalates consisting of K+-H−-K+ triple atomic layer sandwiches which are inserted between metallic graphite sheets. The inserted two-dimensional hydrogen layer is suggested to consist of H ions with a weakly metallic nature. The superconductivity of the hydrogenated potassium-GIC is also discussed in terms of the change in the electronic and lattice dynamical properties by hydrogen uptake. The hydrogen-absorption in alkali-metal-GIC's is an interesting phenomenon in comparison with that in transition metal hydrides from the point of hydrogen storage. The hydrogen-alkali-metal-ternary GIC's obtained from hydrogen absorption have novel electronic properties and lattice structures which provide attractive problems for GIC research. The studies of hydrogen-alkali-metal ternary GIC's are reviewed in this article.

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Ong, T. P., Fulin Xiong, R. P. H. Chang, and C. W. White. "Nucleation and growth of diamond on carbon-implanted single crystal copper surfaces." Journal of Materials Research 7, no. 9 (September 1992): 2429–39. http://dx.doi.org/10.1557/jmr.1992.2429.

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The nucleation and growth of diamond crystals on single crystal copper surfaces has been studied. Microwave plasma enhanced chemical vapor deposition (MPECVD) was used for diamond nucleation and growth. Prior to diamond nucleation, the single crystal copper surface is modified by carbon ion implantation at an elevated temperature (∊820 °C). This procedure leads to the formation of a graphite film on the copper surface, resulting in an enhancement of diamond crystallite nucleation. A simple lattice model has been constructed to describe the mechanism of diamond nucleation on graphite as 〈111〉diamond parallel to 〈0001〉graphite and 〈110〉diamond parallel to 〈11$\overline 1$0〉graphite. This leads to a good understanding of diamond growth on carbon-implanted copper surfaces.

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Bao, Chenguang, Qing Zeng, Fujin Li, Lei Shi, Wei Wu, Li Yang, Yuxi Chen, and Hongbo Liu. "Effect of Boron Doping on the Interlayer Spacing of Graphite." Materials 15, no. 12 (June 13, 2022): 4203. http://dx.doi.org/10.3390/ma15124203.

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Boron-doped graphite was prepared by the heat treatment of coke using B4C powder as a graphitization catalyst to investigate the effects of the substitutional boron atoms on the interlayer spacing of graphite. Boron atoms can be successfully incorporated into the lattice of graphite by heat treatment, resulting in a reduction in the interlayer spacing of graphite to a value close to that of ideal graphite (0.3354 nm). With an increase in the catalyst mass ratio, the content of substituted boron in the samples increased significantly, causing a decrease in the interlayer spacing of the boron-doped graphite. Density functional theory calculations suggested that the effects of the substitutional boron atoms on the interlayer spacing of the graphite may be attributed to the transfer of Π electrons between layers, the increase in the electrostatic surface potential of the carbon layer due to the electron-deficient nature of boron atoms, and Poisson contraction along the c-axis.

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Journal articles on the topic 'Graphite lattice'

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