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Journal articles on the topic 'Allotropie'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 March 2023

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1

Pezoldt, Jörg. "Formation of Different Carbon Phases on SiC." Materials Science Forum 615-617 (March 2009): 227–30. http://dx.doi.org/10.4028/www.scientific.net/msf.615-617.227.

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Carbon is able to crystallise in different allotrope modifications. They mainly differ in the dominating bindings formed in dependence on the hybridization sp, sp2 and sp3 of the carbon atoms. The present work demonstrates the formation of two different forms of car¬bon allotropes by heating both polar surfaces of on axis 6H-SiC(0001) and 6H-SiC(000 ) crystals to temperatures above 1600°C. In consequence of the structural evolution graphite-like (sp2-hybridised) and carbine-like (sp-hybridised) allotropic carbon modifications were obtained.

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2

Wynnyckyj, J. R., and C. G. Morris. "A shear-type allotropie transformation in alumina." Metallurgical Transactions B 16, no. 2 (June 1985): 345–53. http://dx.doi.org/10.1007/bf02679726.

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3

Deinum, H. W. "Zur Frage der Allotropie des Flüssigen Benzols." Recueil des Travaux Chimiques des Pays-Bas 53, no. 11 (September 3, 2010): 1061–63. http://dx.doi.org/10.1002/recl.19340531109.

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4

Sokołowski, M., A. Sokołowska, M. Wronikowski, and T. Kosik. "Allotropie phase transformation induced by UV power laser irradiation of boron nitride." Journal of Materials Science 25, no. 1 (January 1990): 263–67. http://dx.doi.org/10.1007/bf00544218.

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5

Gnanaraj, Leena Rosalind Mary, and Deepa Ganesan. "Topological Study of 6.82 D Carbon Allotrope Structure." Symmetry 14, no. 5 (May 18, 2022): 1037. http://dx.doi.org/10.3390/sym14051037.

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Carbonallotropes are widely available and can be found in the atmosphere, the earth’s crust, and in living creatures in myriad forms. Allotropes are also used in several fields, including for medicinal and biological applications, due to their intriguing properties such as low resistance, high electron mobility, abnormal quantum hall effect, unconventional superconductivity in graphene, and so on. The theoretical analysis of carbon allotropes can hence be quite useful as it leads to a better understanding of the nature and behavior of these ubiquitous materials and also opens the door for even better applications. The objective of this research is to theoretically analyze the carbon allotrope by using four kinds of vertex degree based (VDB) topological indices (Tis), namely VDB multiplicative topological indices, VDB indices using M-Polynomial, VDB entropy measures, and irregularity indices. This analysis will extend the current body of knowledge available for this allotrope and help future researchers in the synthesis of new allotropes.

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6

Impellizzeri, A., A. A. Vorfolomeeva, N. V. Surovtsev, A. V. Okotrub, C. P. Ewels, and D. V. Rybkovskiy. "Simulated Raman spectra of bulk and low-dimensional phosphorus allotropes." Physical Chemistry Chemical Physics 23, no. 31 (2021): 16611–22. http://dx.doi.org/10.1039/d1cp02636d.

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The Placzek approximation with DFT accurately reproduces experimental Raman spectra for phosphorus allotropes. We explain bulk allotrope spectral features in black and white phosphorus, and predict spectra for phosphorus nanostructures.

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7

Sakai, Hiroshi, Hiroshi Sera, and Satoru Nakashima. "Mössbauer and X-ray diffraction studies of an allotropie form of tin, “α2-Sn”." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 76, no. 1-4 (April 1993): 350–51. http://dx.doi.org/10.1016/0168-583x(93)95234-v.

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8

Shawki, E. E., S. N. Flengas, and D. R. Sadoway. "Drop calorimetry of the compounds NbCl5, TaCl5, RbNbCl6, CsNbCl6, RbTaCl6, and CsTaCl6." Canadian Journal of Chemistry 67, no. 7 (July 1, 1989): 1193–99. http://dx.doi.org/10.1139/v89-180.

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Enthalpy contents for NbCl5, TaCl5, RbNbCl6, CsNbCl6, RbTaCl6, and CsTaCl6 were measured as functions of temperature using a high temperature aluminum block drop calorimeter. It was found that the solid compounds RbNbCl6, CsNbCl6, RbTaCl6, and CsTaCl6 undergo allotropie solid–solid transformations and the enthalpies and entropies associated with these phase changes, as well as from fusion, have been evaluated.Molar heat capacities for the systems investigated are reported as linear functions of temperature.The molar heat capacities for solid and molten NbCl5 or TaCl5 were used together with available vapour pressure data to express enthalpies and free energies of vaporization for these compounds as functions of temperature through the third law calculation method. Keywords: calorimetry, heat capacities, transition enthalpies, niobium compounds, tantalum compounds.

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9

Rickhaus, Michel, Marcel Mayor, and Michal Juríček. "Chirality in curved polyaromatic systems." Chemical Society Reviews 46, no. 6 (2017): 1643–60. http://dx.doi.org/10.1039/c6cs00623j.

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Chiral non-planar polyaromatic systems that display zero, positive or negative Gaussian curvature are analysed and their potential to ‘encode’ chirality of larger sp²-carbon allotropes is evaluated. Shown is a hypothetical peanut-shaped carbon allotrope, where helical chirality results from the interplay of various curvature types.

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10

Yap, Stephanie Hui Kit, Kok Ken Chan, Swee Chuan Tjin, and Ken-Tye Yong. "Carbon Allotrope-Based Optical Fibers for Environmental and Biological Sensing: A Review." Sensors 20, no. 7 (April 5, 2020): 2046. http://dx.doi.org/10.3390/s20072046.

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Recently, carbon allotropes have received tremendous research interest and paved a new avenue for optical fiber sensing technology. Carbon allotropes exhibit unique sensing properties such as large surface to volume ratios, biocompatibility, and they can serve as molecule enrichers. Meanwhile, optical fibers possess a high degree of surface modification versatility that enables the incorporation of carbon allotropes as the functional coating for a wide range of detection tasks. Moreover, the combination of carbon allotropes and optical fibers also yields high sensitivity and specificity to monitor target molecules in the vicinity of the nanocoating surface. In this review, the development of carbon allotropes-based optical fiber sensors is studied. The first section provides an overview of four different types of carbon allotropes, including carbon nanotubes, carbon dots, graphene, and nanodiamonds. The second section discusses the synthesis approaches used to prepare these carbon allotropes, followed by some deposition techniques to functionalize the surface of the optical fiber, and the associated sensing mechanisms. Numerous applications that have benefitted from carbon allotrope-based optical fiber sensors such as temperature, strain, volatile organic compounds and biosensing applications are reviewed and summarized. Finally, a concluding section highlighting the technological deficiencies, challenges, and suggestions to overcome them is presented.

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11

Knapp, J. A., and D. M. Follstaedt. "Rapid e-beam heating for studying metastable transitions in Mn." Journal of Materials Research 4, no. 6 (December 1989): 1393–97. http://dx.doi.org/10.1557/jmr.1989.1393.

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We have used rapid e-beam heating and quenching to study metastable transitions between allotropic phases in Mn and to determine relative rates of transformation between the allotropes. The equilibrium α ⇉ β transition at 720 °C is bypassed and the metastable α ⇉ γ transition is observed to occur at a temperature (880 ± 30 °C) near that predicted thermodynamically (864 °C).

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12

JOYA, M. R., A. R. ZANATTA, and J. BARBA-ORTEGA. "RAMAN SPECTROSCOPY OF TEMPERATURE INDUCED EFFECTS IN FOUR CARBON ALLOTROPES." Modern Physics Letters B 27, no. 28 (October 24, 2013): 1350203. http://dx.doi.org/10.1142/s0217984913502035.

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In this paper, we report strong variations in the Raman spectra of different carbon allotropes samples, for temperatures ranging from 83 K to 1123 K. The temperature dependence of D and G peak frequencies in the Raman spectrum of diamond, graphite, graphene, and carbon nanoparticles (CNPs) with 20 nm dot-size were investigated. These effects caused by temperature can be estimated from the changes in position [Formula: see text] and in linewidth of peak full width at half maximum (FWHM) G in the Raman spectrum of each sample. The broadening for each allotrope under the same conditions of temperature were: diamond ~ 4 cm-1, graphite ~ 50 cm-1, graphene ~ 5 cm-1 and nanoparticles ~ 7 cm-1. We also used scanning electron microscopy (SEM) to study the morphology and determine the size of the samples. According to the experimental data, the residual structural disorder and stress present in the samples are enhanced with temperature and responds for the observed changes in the Raman spectra. We present a systematic study of the temperature-dependent Raman spectra of four carbon allotropes.

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13

DI, You-Ying, Qi YANG, Chun-Sheng ZHOU, Cheng-Fang QIAO, Xiao-Wei CUI, and Sheng-Li GAO. "The Allotropes of Nonmetallic Elements (Ⅰ):An Overview of Hydrogen and Boron Allotrope." University Chemistry 32, no. 9 (2017): 21–34. http://dx.doi.org/10.3866/pku.dxhx201704022.

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14

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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15

Liu, Xinye, Gad Licht, Xirui Wang, and Stuart Licht. "Controlled Growth of Unusual Nanocarbon Allotropes by Molten Electrolysis of CO2." Catalysts 12, no. 2 (January 21, 2022): 125. http://dx.doi.org/10.3390/catal12020125.

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This study describes a world of new carbon “fullerene” allotropes that may be synthesized by molten carbonate electrolysis using greenhouse CO2 as the reactant. Beyond the world of conventional diamond, graphite and buckyballs, a vast array of unique nanocarbon structures exist. Until recently, CO2 was thought to be unreactive. Here, we show that CO2 can be transformed into distinct nano-bamboo, nano-pearl, nano-dragon, solid and hollow nano-onion, nano-tree, nano-rod, nano-belt and nano-flower morphologies of carbon. The capability to produce these allotropes at high purity by a straightforward electrolysis, analogous to aluminum production splitting of aluminum oxide, but instead nanocarbon production by splitting CO2, opens an array of inexpensive unique materials with exciting new high strength, electrical and thermal conductivity, flexibility, charge storage, lubricant and robustness properties. Commercial production technology of nanocarbons had been chemical vapor deposition, which is ten-fold more expensive, generally requires metallo-organics reactants and has a highly carbon-positive rather than carbon-negative footprint. Different nanocarbon structures were prepared electrochemically by variation of anode and cathode composition and architecture, electrolyte composition, pre-electrolysis processing and current ramping and current density. Individual allotrope structures and initial growth mechanisms are explored by SEM, TEM, HAADF EDX, XRD and Raman spectroscopy.

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16

Galimberti, M., V. Barbera, S. Guerra, and A. Bernardi. "FACILE FUNCTIONALIZATION OF sp2 CARBON ALLOTROPES WITH A BIOBASED JANUS MOLECULE." Rubber Chemistry and Technology 90, no. 2 (June 1, 2017): 285–307. http://dx.doi.org/10.5254/rct.17.82665.

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ABSTRACT A simple, versatile, sustainable, not expensive method for the functionalization of sp2 carbon allotropes, both nano-sized and nano-structured, without altering their bulk crystalline organization, is presented. Carbon materials available at the commercial scale were used: furnace carbon black (CB), nano-sized graphite with high surface area, and multiwalled carbon nanotubes. A bio-sourced molecule, 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (serinol pyrrole), was used for the functionalization. Serinol pyrrole (SP) was obtained from serinol through a reaction with atomic efficiency of about 82%, performed in the absence of solvents or catalysts. Synthesis of serinol pyrrole was performed as well on carbon allotropes as the solid support. Adducts of serinol pyrrole with a carbon allotrope were prepared with the help of either thermal or mechanical energy. Functionalization yield was in all cases larger than 90%. With such adducts, stable dispersions in water and in NR latex were prepared. A few layers of graphene were isolated from the water dispersions, and NR-based composites precipitated from the latex revealed very even distribution of fine graphitic particles. Composites were prepared, based on NR, IR, and BR as the rubbers and CB and silica as the fillers, with different amounts of CB–SP adduct, and were cross-linked with a sulfur-based system without observing appreciable effect of functionalization on vulcanization kinetics. The CB–SP adduct led to appreciable reduction of the Payne effect.

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17

Gao, Jingrong, Shan He, Anindya Nag, and Jonathan Woon Chung Wong. "A Review of the Use of Carbon Nanotubes and Graphene-Based Sensors for the Detection of Aflatoxin M1 Compounds in Milk." Sensors 21, no. 11 (May 21, 2021): 3602. http://dx.doi.org/10.3390/s21113602.

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This paper presents a comprehensive review of the detection of aflatoxin compounds using carbon allotrope-based sensors. Although aflatoxin M1 and its derivative aflatoxin B1 compounds have been primarily found in milk and other food products, their presence above a threshold concentration causes disastrous health-related anomalies in human beings, such as growth impairment, underweight and even carcinogenic and immunosuppressive effects. Among the many sensors developed to detect the presence of these compounds, the employment of certain carbon allotropes, such as carbon nanotubes (CNTs) and graphene, has been highly preferred due to their enhanced electromechanical properties. These conductive nanomaterials have shown excellent quantitative performance in terms of sensitivity and selectivity for the chosen aflatoxin compounds. This paper elucidates some of the significant examples of the CNTs and graphene-based sensors measuring Aflatoxin M1 (ATM1) and Aflatoxin B1 (AFB1) compounds at low concentrations. The fabrication technique and performance of each of the sensors are shown here, as well as some of the challenges existing with the current sensors.

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18

Suryana, Nana. "Kajian Pengaruh Temperatur Sintering terhadap Peningkatan Derajat Kristalinitas Karbon dari Limbah Kulit Kemiri." Jurnal Ilmu dan Inovasi Fisika 5, no. 2 (August 9, 2021): 164–69. http://dx.doi.org/10.24198/jiif.v5i2.35078.

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Allotropes of carbon has advantages in the ability to intercalate ions, atoms or molecules that potentially to apply in various technological applications. Graphite one of allotrope carbon which has well intercalation and ion transport capabilities. In case, the synthesis of activated carbon made from candlenut shell was carried out with carbonization temperatures at 700C and used a chemical activator in form of 30% KOH. After the activation process, given the sintering treatment for activating carbon with temperature of 950C and 1000C, respectively, which this process is expected to increase the crystalline phase of activated carbon close to the graphite phase. The result showed that dominantion of the structures were amorphous, with varying degrees of crystallinity ranging 35.23% and 35.44%, respectively, and the degrees of graphitization 36% and 37% for the vertical and horizontal directions, respectively. The treatment of the sintering process with a temperature of 1000C has the highest degree of crystallinity, 35.44%. This indicates that the sintering process has an effect on the activated carbon

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19

Ng, Kean Pin, Kia Wai Liew, and Elaine Lim. "Comparative Study of Tribological Properties of Modified and Non-modified Graphene-Oil Nanofluids under Heated and Non-heated Conditions." Lubricants 10, no. 11 (October 31, 2022): 288. http://dx.doi.org/10.3390/lubricants10110288.

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With the aim of achieving more effective friction and wear reduction in sliding bearing applications, surface-modified graphene, which exhibits better dispersion stability than non-modified graphene, was synthesized and applied in this study using various graphene allotropes, including graphene nanoplatelets (GNP), multiwalled carbon nanotubes (MWCNT) and nanostructured graphite (NSG). Friction and wear tests of each type of graphene allotrope under modified and non-modified conditions were studied using a pin-on-ring tribo tester. In addition, the dynamic viscosity of each synthesized nanofluid sample was measured using a falling-ball viscometer. A series of modified graphene-oil nanofluids and non-modified graphene-oil nanofluids were prepared and heated before their friction and wear performance was investigated at room temperature. Friction and wear behavior, as well as the dynamic viscosity of the heated nanofluids vary insignificantly when compared to those of the non-heated nanofluids. The results showed that the best friction and wear reduction was achieved by modified GNP with friction and wear reduction of 60.5% and 99.4%, respectively.

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20

Jana, Susmita, Arka Bandyopadhyay, Sujoy Datta, Debaprem Bhattacharya, and Debnarayan Jana. "Emerging properties of carbon based 2D material beyond graphene." Journal of Physics: Condensed Matter 34, no. 5 (November 10, 2021): 053001. http://dx.doi.org/10.1088/1361-648x/ac3075.

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Abstract Graphene turns out to be the pioneering material for setting up boulevard to a new zoo of recently proposed carbon based novel two dimensional (2D) analogues. It is evident that their electronic, optical and other related properties are utterly different from that of graphene because of the distinct intriguing morphology. For instance, the revolutionary emergence of Dirac cones in graphene is particularly hard to find in most of the other 2D materials. As a consequence the crystal symmetries indeed act as a major role for predicting electronic band structure. Since tight binding calculations have become an indispensable tool in electronic band structure calculation, we indicate the implication of such method in graphene’s allotropes beyond hexagonal symmetry. It is to be noted that some of these graphene allotropes successfully overcome the inherent drawback of the zero band gap nature of graphene. As a result, these 2D nanomaterials exhibit great potential in a broad spectrum of applications, viz nanoelectronics, nanooptics, gas sensors, gas storages, catalysis, and other specific applications. The miniaturization of high performance graphene allotrope based gas sensors to microscopic or even nanosized range has also been critically discussed. In addition, various optical properties like the dielectric functions, optical conductivity, electron energy loss spectra reveal that these systems can be used in opto-electronic devices. Nonetheless, the honeycomb lattice of graphene is not superconducting. However, it is proposed that the tetragonal form of graphene can be intruded to form new hybrid 2D materials to achieve novel superconducting device at attainable conditions. These dynamic experimental prospects demand further functionalization of these systems to enhance the efficiency and the field of multifunctionality. This topical review aims to highlight the latest advances in carbon based 2D materials beyond graphene from the basic theoretical as well as future application perspectives.

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21

Bondarchuk, Sergey V., and Boris F. Minaev. "Super high-energy density single-bonded trigonal nitrogen allotrope—a chemical twin of the cubic gauche form of nitrogen." Physical Chemistry Chemical Physics 19, no. 9 (2017): 6698–706. http://dx.doi.org/10.1039/c6cp08723j.

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A new ambient-pressure metastable single-bonded nitrogen allotrope was predicted using reliable theoretical methods. The predicted allotrope has a number of similarities with the experimentally detected cubic gauche nitrogen allotrope.

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22

Sun, Ya-Ping. "(Invited) Nanoscale Carbon Allotrope at Zero-Dimension – Small Carbon Nanoparticles Versus Molecular Fullerenes." ECS Meeting Abstracts MA2022-01, no. 11 (July 7, 2022): 826. http://dx.doi.org/10.1149/ma2022-0111826mtgabs.

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In the vast research field on carbon nanostructures, a seemingly broadly accepted family configuration of nanoscale carbon allotropes is such that fullerenes take the zero-dimensional dot spot, in perfect harmony with one-dimensional carbon nanotubes and two-dimensional graphene nanosheets. More recently, however, a threat to the nice “family value” has been the emergence of small carbon nanoparticles, which are carbon particles of a few nanometers in size without any defined crystal structures or largely amorphous and populated with abundant surface and other defects. The growing experimental evidence has revealed the unique and/or advantageous optical and photoexcited state properties and photoinduced redox characteristics of the small carbon nanoparticles, elevating them to the position of being able to compete with fullerenes for the title of nanoscale carbon allotrope at the zero-dimension. Moreover, a related supporting argument is that fullerenes are molecules, nanoscale in their sizes but not necessarily “nanomaterials” strictly speaking. In this presentation, relevant experimental results of the nanoparticles and fullerenes will be compared for a fair assessment and judgment of their title competition, and more importantly their shared structural features and electronic properties and also their enormous potential in the development of materials for a variety of technological applications will be highlighted.

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23

Li, Qi, Aigen Li, B. W. Jiang, and Tao Chen. "On carbon nanotubes in the interstellar medium." Monthly Notices of the Royal Astronomical Society 493, no. 2 (February 17, 2020): 3054–59. http://dx.doi.org/10.1093/mnras/staa467.

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ABSTRACT Since their discovery in 1991, carbon nanotubes (CNTs) – a novel one-dimensional carbon allotrope – have attracted considerable interest worldwide because of their potential technological applications such as electric and optical devices. In the astrophysical context, CNTs may be present in the interstellar space since many of the other allotropes of carbon (e.g. amorphous carbon, fullerenes, nanodiamonds, graphite, polycyclic aromatic hydrocarbons, and possibly graphene as well) are known to be widespread in the Universe, as revealed by pre-solar grains in carbonaceous primitive meteorites and/or by their fingerprint spectral features in astronomical spectra. In addition, there are also experimental and theoretical pathways to the formation of CNTs in the interstellar medium (ISM). In this work, we examine their possible presence in the ISM by comparing the observed interstellar extinction curve with the ultraviolet/optical absorption spectra experimentally obtained for single-walled CNTs of a wide range of diameters and chiralities. Based on the absence in the interstellar extinction curve of the ${\sim}$4.5 and 5.25 ${\rm eV} \ \pi$-plasmon absorption bands that are pronounced in the experimental spectra of CNTs, we place an upper limit of ${\sim}10\, {\rm ppm}$ of C/H (i.e. ${\sim}$4 per cent of the total interstellar C) on the interstellar CNT abundance.

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Chen, Tao, and Aigen Li. "Synthesizing carbon nanotubes in space." Astronomy & Astrophysics 631 (October 18, 2019): A54. http://dx.doi.org/10.1051/0004-6361/201935789.

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Context. As the fourth most abundant element in the universe, carbon (C) is widespread in the interstellar medium (ISM) in various allotropic forms (e.g. fullerenes have been identified unambiguously in many astronomical environments, the presence of polycyclic aromatic hydrocarbon molecules in space has been commonly acknowledged, and presolar graphite, as well as nanodiamonds, have been identified in meteorites). As stable allotropes of these species, whether carbon nanotubes (CNTs) and their hydrogenated counterparts are also present in the ISM or not is unknown. Aims. The aim of the present works is to explore the possible routes for the formation of CNTs in the ISM and calculate their fingerprint vibrational spectral features in the infrared (IR). Methods. We studied the hydrogen-abstraction and acetylene-addition (HACA) mechanism and investigated the synthesis of nanotubes using density functional theory (DFT). The IR vibrational spectra of CNTs and hydrogenated nanotubes (HNTs), as well as their cations, were obtained with DFT. Results. We find that CNTs could be synthesized in space through a feasible formation pathway. CNTs and cationic CNTs, as well as their hydrogenated counterparts, exhibit intense vibrational transitions in the IR. Their possible presence in the ISM could be investigated by comparing the calculated vibrational spectra with astronomical observations made by the Infrared Space Observatory, Spitzer Space Telescope, and particularly the upcoming James Webb Space Telescope.

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25

Hernandez, Angela, and Lizabeth Paravisini-Gebert. "Allotropes." Callaloo 23, no. 3 (2000): 987–94. http://dx.doi.org/10.1353/cal.2000.0159.

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26

Pan, Bitao, Jun Xiao, Jiling Li, Pu Liu, Chengxin Wang, and Guowei Yang. "Carbyne with finite length: The one-dimensional sp carbon." Science Advances 1, no. 9 (October 2015): e1500857. http://dx.doi.org/10.1126/sciadv.1500857.

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Carbyne is the one-dimensional allotrope of carbon composed of sp-hybridized carbon atoms. Definitive evidence for carbyne has remained elusive despite its synthesis and preparation in the laboratory. Given the remarkable technological breakthroughs offered by other allotropes of carbon, including diamond, graphite, fullerenes, carbon nanotubes, and graphene, interest in carbyne and its unusual potential properties remains intense. We report the first synthesis of carbyne with finite length, which is clearly composed of alternating single bonds and triple bonds, using a novel process involving laser ablation in liquid. Spectroscopic analyses confirm that the product is the structure of sp hybridization with alternating carbon-carbon single bonds and triple bonds and capped by hydrogen. We observe purple-blue fluorescence emissions from the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital of carbyne. Condensed-phase carbyne crystals have a hexagonal lattice and resemble the white crystalline powder produced by drying a carbyne solution. We also establish that the combination of gold and alcohol is crucial to carbyne formation because carbon-hydrogen bonds can be cleaved with the help of gold catalysts under the favorable thermodynamic environment provided by laser ablation in liquid and because the unique configuration of two carbon atoms in an alcohol molecule matches the elementary entity of carbyne. This laboratory synthesis of carbyne will enable the exploration of its properties and applications.

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Tatullo, Marco, Barbara Zavan, Fabio Genovese, Bruna Codispoti, Irina Makeeva, Sandro Rengo, Leonzio Fortunato, and Gianrico Spagnuolo. "Borophene Is a Promising 2D Allotropic Material for Biomedical Devices." Applied Sciences 9, no. 17 (August 21, 2019): 3446. http://dx.doi.org/10.3390/app9173446.

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Allotropic 2D materials are the new frontier of materials science, due to their unique strategic properties and application within several sciences. Allotropic 2D materials have shown tunable physical, chemical, biochemical, and optical characteristics, and among the allotropic materials, graphene has been widely investigated for its interesting properties, which are highly required in biomedical applications. Recently, the synthesis of thin 2D boron sheets, developed on Ag(111) substrates, was able to create a 2D triangular structure called borophene (BO). Borophene has consistently shown anisotropic behavior similar to graphene. In this topical review, we will describe the main properties and latest applications of borophene. This review will critically describe the most interesting uses of borophene as part of electronic and optical circuits. Moreover, we will report how borophene can be an innovative component of sensors within biomedical devices, and we will discuss its use in nanotechnologies and theranostic applications. The conclusions will provide insight into the latest frontiers of translational medicine involving this novel and strategic 2D allotropic material.

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28

Mitura, Katarzyna, Joanna Kornacka, Elżbieta Kopczyńska, Jacek Kalisz, Ewa Czerwińska, Maciej Affeltowicz, Witold Kaczorowski, et al. "Active Carbon-Based Nanomaterials in Food Packaging." Coatings 11, no. 2 (January 29, 2021): 161. http://dx.doi.org/10.3390/coatings11020161.

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Carbon-based nanomaterials (CBN) are currently used in many biomedical applications. The research includes optimization of single grain size and conglomerates of pure detonated nanodiamond (DND), modified nanodiamond particles and graphene oxide (GO) in order to compare their bactericidal activity against food pathogens. Measurement of grain size and zeta potential was performed using the Dynamic Light Scattering (DLS) method. Surface morphology was evaluated using a Scanning Electron Microscope (SEM) and confocal microscope. X-ray diffraction (XRD) was performed in order to confirm the crystallographic structure of detonation nanodiamond particles. Bacteriostatic tests were performed by evaluating the inhibition zone of pathogens in the presence of carbon based nanomaterials. Raman spectroscopy showed differences between the content of the diamond and graphite phases in diamond nanoparticles. Fluorescence microscopy and adenosine-5′-triphosphate (ATP) determination methods were used to assess the bactericidal of bioactive polymers obtained by modification of food wrapping film using various carbon-based nanomaterials. The results indicate differences in the sizes of individual grains and conglomerates of carbon nanomaterials within the same carbon allotropes depending on surface modification. The bactericidal properties depend on the allotropic form of carbon and the type of surface modification. Depending on the grain size of carbon-based materials, surface modification, the content of the diamond and graphite phases, surface of carbon-based nanomaterials film formation shows more or less intense bactericidal properties and differentiated adhesion of bacterial biofilms to food films modified with carbon nanostructures.

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Stewart, Anna, Erin E. Taylor, and Nicholas P. Stadie. "A Search for New Mesoporous Carbon Solids with Cubic Ordered Porosity." ECS Meeting Abstracts MA2022-01, no. 55 (July 7, 2022): 2243. http://dx.doi.org/10.1149/ma2022-01552243mtgabs.

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A three-dimensional material comprised exclusively of carbon whose underlying structure lies on a triply periodic minimal surface (TPMS) is a member of the class of hypothetical carbon allotropes known as schwarzites. Such materials are highly sought-after due to their fundamental significance (the last remaining unknown crystalline allotrope of sp2-hybridized carbon) and likely interesting properties (e.g., ballistic conduction at room temperature). Other properties include a large pore volume and high surface area for gas and ion adsorption, making them a class of candidate materials for many applications such as supercapacitor electrodes and gas storage. A true schwarzite has never been synthesized, despite their predicted low energies of formation compared to fullerenes. This research focuses on the synthesis of an interpenetrating schwarzite-like material. A hard-templating strategy has been designed to achieve this through the synthesis of a free-standing graphene foam material whose structure lies on a cubic TPMS. The specific material of interest herein requires an ordered mesoporous silicate template that carries the Ia-3d space group with an optimal pore to wall ratio. Pore and wall structure as well as composition for these materials can be optimized by changing the hydrothermal synthesis temperature, the addition of different precursors, and by varying the cationic and neutral structure-directing agents. We present our recent progress in this effort and also propose future work to achieve optimal templates for schwarzite-like materials synthesis. Figure 1

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30

Khan, Muhammad Rizwan, Kun Bu, and Jian-Tao Wang. "Topological nodal line semimetal in an all-sp ² monoclinic carbon." New Journal of Physics 24, no. 4 (April 1, 2022): 043007. http://dx.doi.org/10.1088/1367-2630/ac5e16.

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Abstract Topological nodal line semimetal is an exotic class of quantum materials featuring the continuous line of nodes inside the first Brillouin zone. Here we identify by systematical ab initio calculations a new all-sp 2 hybridized carbon allotrope with monoclinic C2/c ( C 2 h 6 ) symmetry which is termed as bcm-C16. Total energy calculations show that our proposed bcm-C16 carbon is energetically comparable to or stable than the previously proposed bco-C16, bct-C16, and oP16 carbon. Its dynamical stability has been confirmed by phonon mode calculations. Detailed analysis of the electronic properties show that bcm-C16 carbon is a topological nodal line semimetal with a single closed nodal ring around the Γ high symmetric point, protected by spatial inversion ( P ) and time-reversal ( T ) symmetry. When the nodal ring is projected onto the (001) surface, a topologically protected drumhead-like surface state can be seen inside or outside the nodal ring depending on the different surface terminations. Moreover, we also examined the tensile-strain robustness of the electronic properties of bcm-C16 carbon. The nodal ring is robust under a tensile-strain along the crystalline x- and z-directions up to 20%. In addition, the simulated x-ray diffraction pattern (XRD) of bcm-C16 carbon matches with the experimental pattern found in the detonation and chimney soot experiment. The present proposal has enriched the family of carbon allotropes with topological nodal lines, and pave the way for further theoretical and experimental studies.

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31

Chen, Xue-Kun, Xiao-Yan Hu, Pin-Zhen Jia, and Guo-Feng Xie. "First-principles determination of high thermal conductivity of PCF-graphene: A comparison with graphene." Applied Physics Letters 121, no. 18 (October 31, 2022): 182205. http://dx.doi.org/10.1063/5.0123629.

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Poly-cyclooctatetraene framework (PCF)-graphene, an emerging all-sp2 hybridized two-dimensional (2D) carbon allotrope, possesses an intrinsic direct bandgap (0.77 eV) and excellent mechanical properties, indicating great potential in nanoelectronics. Understanding the thermal transport behavior of PCF-graphene is of vital importance for determining the reliability of related devices based on it. In this work, the thermal transport in PCF-graphene is systematically studied using the Boltzmann transport theory combined with first-principles calculations. The results show that the room-temperature thermal conductivity of PCF-graphene with only considering three-phonon scattering is as high as 1587.3 W/m K along the zigzag direction, and decreases by 27.1% (1157.4 W/m K) when including four-phonon scattering, indicating the four-phonon scattering plays a non-negligible role in in thermal transport. Although the thermal conductivity of PCF-graphene is not as large as that in graphene, it still exceeds most common 2D materials and makes it suitable for applications in the thermal management of microelectronics. Analyses of phonon group velocity and phonon scattering rates are conducted to reveal the high thermal conductivity of PCF. Moreover, as the temperature increases to 800 K, the reduction of thermal conductivity is close to 50% after including four-phonon scattering. The analysis of phonon group velocity and phonon scattering rates are conducted to reveal the underlying mechanism. Our results provide insights for constructing high-thermal-conductivity materials based on 2D carbon allotropes.

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32

Nisar, Jawad, Xue Jiang, Biswarup Pathak, Jijun Zhao, Tae Won Kang, and Rajeev Ahuja. "Semiconducting allotrope of graphene." Nanotechnology 23, no. 38 (September 4, 2012): 385704. http://dx.doi.org/10.1088/0957-4484/23/38/385704.

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33

Elguero, José, Concepción Foces-Foces, and Antonio L. Llamas-Saiz. "Another Possible Carbon Allotrope." Bulletin des Sociétés Chimiques Belges 101, no. 9 (September 1, 2010): 795–99. http://dx.doi.org/10.1002/bscb.19921010909.

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34

Millecam, Todd, Austin J. Jarrett, Naomi Young, Dana E. Vanderwall, and Dennis Della Corte. "Coming of age of Allotrope: Proceedings from the Fall 2020 Allotrope Connect." Drug Discovery Today 26, no. 8 (August 2021): 1922–28. http://dx.doi.org/10.1016/j.drudis.2021.03.028.

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35

Enyashin, Andrey N., and Alexander L. Ivanovskii. "Graphene allotropes." physica status solidi (b) 248, no. 8 (January 10, 2011): 1879–83. http://dx.doi.org/10.1002/pssb.201046583.

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36

Zhu, Xi, and Min Wang. "Porous CY carbon: a new semiconducting phase with an sp1–sp2–sp3 bonding network." RSC Advances 6, no. 113 (2016): 112035–39. http://dx.doi.org/10.1039/c6ra18047g.

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37

Okwundu, Onyeka Stanislaus, Emmanuel Uche Aniekwe, and Chinaza Emmanuel Nwanno. "Unlimited potentials of carbon: different structures and uses (a Review)." Metallurgical and Materials Engineering 24, no. 3 (October 19, 2018): 145–71. http://dx.doi.org/10.30544/388.

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Carbon is a unique chemical element whose different forms or allotropes are inexhaustible in number. It has been in use since antiquity and now, the possibility of manipulating the lattice structure of its crystalline allotropes, offers it unlimited advanced applications. This review aims at demonstrating certain aspects of engineering material in different applications. Various structures of some identified allotropes carbon, respective properties and uses of the allotropes were reviewed. Amorphous carbon materials find application mainly as fuels and sometimes as parent materials for synthesis of more useful chemicals. Their limited application was ascribed to their unstable irregular patterned structure which cannot be manipulated easily to meet further needs. Structurally, carbon exists in the sp3 and sp2 hybridized state in the crystal lattice of its crystalline allotropes. Due to the salient features of its allotropes, carbon finds application in energy generation and storage, optics, electronics, opto-electronics, electro-catalysis, corrosion control, bio-sensing (diagnostics), sensing, agriculture, water treatment, making of composite materials with unique properties and more. There is no limit to the application of carbon. It was recommended that renewable and sustainable alternative precursors for synthesis of carbon nanomaterials with crystal growth control be sought for.

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38

Paryzhak, S. Ya, T. I. Dumych, S. M. Peshkova, E. E. Bila, A. D. Lutsyk, A. Barras, R. Boukherroub, S. Szunerits, and R. O. Bilyy. "Interaction of 4 allotropic modifications of carbon nanoparticles with living tissues." Ukrainian Biochemical Journal 91, no. 2 (April 1, 2019): 41–50. http://dx.doi.org/10.15407/ubj91.02.041.

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39

Yastrebov, S. G., and V. I. Ivanov-Omskiĭ. "Allotropic composition of amorphous carbon." Semiconductors 41, no. 8 (August 2007): 946–52. http://dx.doi.org/10.1134/s1063782607080155.

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40

Khokhlov, A. F., A. I. Mashin, and D. A. Khokhlov. "New allotropic form of silicon." Journal of Experimental and Theoretical Physics Letters 67, no. 9 (May 1998): 675–79. http://dx.doi.org/10.1134/1.567700.

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41

Zhuo, Zhiwen, Xiaojun Wu, and Jinlong Yang. "Me-graphene: a graphene allotrope with near zero Poisson's ratio, sizeable band gap, and high carrier mobility." Nanoscale 12, no. 37 (2020): 19359–66. http://dx.doi.org/10.1039/d0nr03869e.

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The exploration of new two-dimensional (2D) allotropes of carbon has attracted great research attention after graphene, but experiment-feasible graphene allotropes with novel properties are still rare.

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42

Delodovici, Francesco, Nicola Manini, Richard S. Wittman, Daniel S. Choi, Mohamed Al Fahim, and Larry A. Burchfield. "Protomene: A new carbon allotrope." Carbon 126 (January 2018): 574–79. http://dx.doi.org/10.1016/j.carbon.2017.10.069.

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43

Nulakani, Naga Venkateswara Rao, and Venkatesan Subramanian. "Superprismane: A porous carbon allotrope." Chemical Physics Letters 715 (January 2019): 29–33. http://dx.doi.org/10.1016/j.cplett.2018.11.006.

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44

Bondarchuk, Sergey V. "Beyond molecular nitrogen: revelation of two ambient-pressure metastable single- and double-bonded nitrogen allotropes built from three-membered rings." Physical Chemistry Chemical Physics 21, no. 41 (2019): 22930–38. http://dx.doi.org/10.1039/c9cp04288a.

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45

Wang, Haipeng, Cheng Liu, Huili Wang, Xinpeng Han, Shaojie Zhang, Jiantong Sun, Yiming Zhang, Yu Cao, Yuan Yao, and Jie Sun. "The synthesis of greenish phosphorus on carbon substrates." Chemical Communications 57, no. 33 (2021): 3975–78. http://dx.doi.org/10.1039/d1cc01419f.

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46

Hu, Menglei, Ziao Wang, Yanheng Xu, Jiechun Liang, Jiagen Li, and Xi Zhu. "fvs-Si48: a direct bandgap silicon allotrope." Physical Chemistry Chemical Physics 20, no. 41 (2018): 26091–97. http://dx.doi.org/10.1039/c8cp03165g.

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47

Abramenko, N. D., and M. A. Rozhkov. "Lattice Design for Non-Carbon Two-Dimensional Allotropic Modifications." Reviews on advanced materials and technologies 3, no. 4 (2021): 19–23. http://dx.doi.org/10.17586/2687-0568-2021-3-4-19-23.

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In this article, an approach to lattice design for two two-dimensional allotropic materials is proposed. The approach is based on the use of crystal lattices of disclinated graphene known as pseudo-graphenes. The approach is demonstrated on pseudo-graphenes G5-7v1 and G5-6-7v2 and target crystals originated from molybdenum disulfide and phosphorene. Geometry optimization done by density functional theory calculations display that the designed lattices for new materials are structurally stable, which means that they could be synthesized and that the new approach could successfully be used to produce lattice designs for novel two-dimensional allotropic materials.

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48

Pereira, M. L., W. F. da Cunha, R. T. de Sousa, G. D. Amvame Nze, D. S. Galvão, and L. A. Ribeiro. "On the mechanical properties and fracture patterns of the nonbenzenoid carbon allotrope (biphenylene network): a reactive molecular dynamics study." Nanoscale 14, no. 8 (2022): 3200–3211. http://dx.doi.org/10.1039/d1nr07959j.

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49

Takahashi, Lauren, and Keisuke Takahashi. "Structural stability and electronic properties of an octagonal allotrope of two dimensional boron nitride." Dalton Transactions 46, no. 13 (2017): 4259–64. http://dx.doi.org/10.1039/c7dt00372b.

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50

Gao, Xin, Huibiao Liu, Dan Wang, and Jin Zhang. "Graphdiyne: synthesis, properties, and applications." Chemical Society Reviews 48, no. 3 (2019): 908–36. http://dx.doi.org/10.1039/c8cs00773j.

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