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Radek Zbořil - One of the best experts on this subject based on the ideXlab platform.
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Chemistry, properties, and applications of fluoroGraphene
Applied Materials Today, 2017Co-Authors: Demetrios D. Chronopoulos, Martin Pykal, Aristides Bakandritsos, Radek Zbořil, Michal OtyepkaAbstract:FluoroGraphene, formally a two-dimensional stoichiometric Graphene derivative, attracted remarkable attention of the scientific community due to its extraordinary physical and chemical properties. We overview the strategies for the preparation of fluorinated Graphene derivatives, based on top-down and bottom-up approaches. The physical and chemical properties of fluoroGraphene, which is considered as one of the thinnest insulators with a wide electronic band gap, are presented. Special attention is paid to the rapidly developing chemistry of fluoroGraphene, which was advanced in the last few years. The unusually high reactivity of fluoroGraphene, which can be chemically considered perfluorinated hydrocarbon, enables facile and scalable access to a wide portfolio of Graphene derivatives, such as Graphene acid, cyanoGraphene and allyl-Graphene. Finally, we summarize the so far reported applications of fluoroGraphene and fluorinated Graphenes, spanning from sensing and bioimaging to separation, electronics and energy technologies.
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Halogenated Graphenes: Rapidly growing family of Graphene derivatives
ACS Nano, 2013Co-Authors: František Karlický, Kasibhatta Kumara Ramanatha Datta, Michal Otyepka, Radek ZbořilAbstract:Graphene derivatives containing covalently bound halogens (Graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp(2) carbons changes the hybridization state to sp(3), which has a principal impact on electronic properties and local structure of the material. The fully fluorinated Graphene derivative, fluoroGraphene (Graphene fluoride, C1F1), is the thinnest insulator and the only stable stoichiometric Graphene halide (C1X1). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluoroGraphene and other partially fluorinated, chlorinated, and brominated Graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of Graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated Graphenes, iodine-doped Graphene, and mixed Graphene halides. Finally, patterned halogenation is presented as an interesting approach for generating materials with applications in the field of Graphene-based electronic devices.
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Graphene fluoride: A stable stoichiometric Graphene derivative and its chemical conversion to Graphene
Small, 2010Co-Authors: Radek Zbořil, Athanasios B. Bourlinos, František Karlický, Theodore A. Steriotis, Dalibor Jančík, Christos Trapalis, Athanasios K. Stubos, Klára Šafářová, Vasilios Georgakilas, Michal OtyepkaAbstract:Stoichoimetric Graphene fluoride monolayers are obtained in a single step by the liquid-phase exfoliation of graphite fluoride with sulfolane. Comparative quantum-mechanical calculations reveal that Graphene fluoride is the most thermodynamically stable of five studied hypothetical Graphene derivatives; graphane, Graphene fluoride, bromide, chloride, and iodide. The Graphene fluoride is transformed into Graphene via Graphene iodide, a spontaneously decomposing intermediate. The calculated bandgaps of Graphene halides vary from zero for Graphene bromide to 3.1 eV for Graphene fluoride. It is possible to design the electronic properties of such two-dimensional crystals.
Michal Otyepka - One of the best experts on this subject based on the ideXlab platform.
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Chemistry, properties, and applications of fluoroGraphene
Applied Materials Today, 2017Co-Authors: Demetrios D. Chronopoulos, Martin Pykal, Aristides Bakandritsos, Radek Zbořil, Michal OtyepkaAbstract:FluoroGraphene, formally a two-dimensional stoichiometric Graphene derivative, attracted remarkable attention of the scientific community due to its extraordinary physical and chemical properties. We overview the strategies for the preparation of fluorinated Graphene derivatives, based on top-down and bottom-up approaches. The physical and chemical properties of fluoroGraphene, which is considered as one of the thinnest insulators with a wide electronic band gap, are presented. Special attention is paid to the rapidly developing chemistry of fluoroGraphene, which was advanced in the last few years. The unusually high reactivity of fluoroGraphene, which can be chemically considered perfluorinated hydrocarbon, enables facile and scalable access to a wide portfolio of Graphene derivatives, such as Graphene acid, cyanoGraphene and allyl-Graphene. Finally, we summarize the so far reported applications of fluoroGraphene and fluorinated Graphenes, spanning from sensing and bioimaging to separation, electronics and energy technologies.
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Halogenated Graphenes: rapidly growing family of Graphene derivatives.
ACS Nano, 2013Co-Authors: František Karlický, Michal Otyepka, K. K. R. Datta, Radek ZbořilAbstract:Graphene derivatives containing covalently bound halogens (Graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp2 carbons changes the hybridization state to sp3, which has a principal impact on electronic properties and local structure of the material. The fully fluorinated Graphene derivative, fluoroGraphene (Graphene fluoride, C1F1), is the thinnest insulator and the only stable stoichiometric Graphene halide (C1X1). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluoroGraphene and other partially fluorinated, chlorinated, and brominated Graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of Graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated Graphenes, iodine-doped Graphene, and mixed Graphene halides. Finally, patterned halogenati...
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Halogenated Graphenes: Rapidly growing family of Graphene derivatives
ACS Nano, 2013Co-Authors: František Karlický, Kasibhatta Kumara Ramanatha Datta, Michal Otyepka, Radek ZbořilAbstract:Graphene derivatives containing covalently bound halogens (Graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp(2) carbons changes the hybridization state to sp(3), which has a principal impact on electronic properties and local structure of the material. The fully fluorinated Graphene derivative, fluoroGraphene (Graphene fluoride, C1F1), is the thinnest insulator and the only stable stoichiometric Graphene halide (C1X1). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluoroGraphene and other partially fluorinated, chlorinated, and brominated Graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of Graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated Graphenes, iodine-doped Graphene, and mixed Graphene halides. Finally, patterned halogenation is presented as an interesting approach for generating materials with applications in the field of Graphene-based electronic devices.
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Graphene fluoride: A stable stoichiometric Graphene derivative and its chemical conversion to Graphene
Small, 2010Co-Authors: Radek Zbořil, Athanasios B. Bourlinos, František Karlický, Theodore A. Steriotis, Dalibor Jančík, Christos Trapalis, Athanasios K. Stubos, Klára Šafářová, Vasilios Georgakilas, Michal OtyepkaAbstract:Stoichoimetric Graphene fluoride monolayers are obtained in a single step by the liquid-phase exfoliation of graphite fluoride with sulfolane. Comparative quantum-mechanical calculations reveal that Graphene fluoride is the most thermodynamically stable of five studied hypothetical Graphene derivatives; graphane, Graphene fluoride, bromide, chloride, and iodide. The Graphene fluoride is transformed into Graphene via Graphene iodide, a spontaneously decomposing intermediate. The calculated bandgaps of Graphene halides vary from zero for Graphene bromide to 3.1 eV for Graphene fluoride. It is possible to design the electronic properties of such two-dimensional crystals.
Y Bu - One of the best experts on this subject based on the ideXlab platform.
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highly efficient photocatalytic performance of Graphene zno quasi shell core composite material
ACS Applied Materials & Interfaces, 2013Co-Authors: Y Bu, Z Chen, Weibing LiAbstract:In the present paper, the Graphene–ZnO composite with quasi-shell–core structure was successfully prepared using a one-step wet chemical method. The photocatalytic Rhodamine B degradation property and the photoelectrochemical performance of the Graphene–ZnO quasi-shell–core composite are dependent on the amount of Graphene oxide that is added. When the amount of Graphene oxide added is 10 mg, the Graphene–ZnO quasi-shell–core composite possesses the optimal photocatalytic degradation efficiency and the best photoelectrochemical performance. An efficient interfacial electric field is established on the interface between the Graphene and ZnO, which significantly improves the separation efficiency of the photogenerated electron–hole pairs and thus dramatically increases its photoelectrochemical performance. In addition to the excellent photocatalytic and photoelectrochemical properties, the electron migration ability of the grephene–ZnO quasi-shell–core composite is significantly enhanced due to the Graphene...
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Highly efficient photocatalytic performance of Graphene-ZnO quasi-shell-core composite material
ACS Appl Mater Interfaces, 2013Co-Authors: Y Bu, Z Chen, Wei Li, B. HouAbstract:In the present paper, the Graphene-ZnO composite with quasi-shell-core structure was successfully prepared using a one-step wet chemical method. The photocatalytic Rhodamine B degradation property and the photoelectrochemical performance of the Graphene-ZnO quasi-shell-core composite are dependent on the amount of Graphene oxide that is added. When the amount of Graphene oxide added is 10 mg, the Graphene-ZnO quasi-shell-core composite possesses the optimal photocatalytic degradation efficiency and the best photoelectrochemical performance. An efficient interfacial electric field is established on the interface between the Graphene and ZnO, which significantly improves the separation efficiency of the photogenerated electron-hole pairs and thus dramatically increases its photoelectrochemical performance. In addition to the excellent photocatalytic and photoelectrochemical properties, the electron migration ability of the grephene-ZnO quasi-shell-core composite is significantly enhanced due to the Graphene coating on ZnO surface; therefore, this material has great potential for application as a substrate material to accept electrons in dye solar cell and in narrow bandgap semiconductor quantum dot sensitized solar cells.
C. N. R. Rao - One of the best experts on this subject based on the ideXlab platform.
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Graphene: Synthesis, Properties, and Phenomena - Graphene: Synthesis, Properties, and Phenomena
2012Co-Authors: C. N. R. Rao, A. K. SoodAbstract:PREFACE SYNTHESIS, CHARACTERIZATION, AND SELECTED PROPERTIES OF Graphene Introduction Synthesis of Single-Layer and Few-Layered Graphenes Synthesis of Graphene Nanoribbons Selected Properties Inorganic Graphene Analogs UNDERSTANDING Graphene VIA RAMAN SCATTERING Introduction Atomic Structure and Electronic Structure of Graphene Phonons and Raman Modes in Graphene Layer Dependence of Raman Spectra Phonon Renormalization Due to Electron and Hole Doping of Graphene Raman Spectroscopy of Graphene Edges and Graphene Nanoribbons Effect of Disorder on the Raman Spectrum of Graphene Raman Spectroscopy of Graphene under Strain Temperature and Pressure Dependence of Raman Modes in Graphene as Nanometrological Tools Tip-Enhanced Raman Spectroscopy of Graphene Layers Conclusions PHYSICS OF QUANTA AND QUANTUM FIELDS IN Graphene Introduction Dirac Theory in 3 + 1 Dimensions: A Review Band Structure of Graphene: Massless Chiral Dirac Electrons in 2 + 1 Dimensions Anomaly - A Brief Introduction Graphene and 2 + 1-Dimensional Parity Anomaly Zitterbewegung Klein Paradox Relativistic-Type Effects and Vacuum Collapse in Graphene in Crossed Electric and Magnetic Fields Prediction of Spin-1 Quanta from Resonating Valence Bond Correlations Majorana Zero Mode from Two-Channel Kondo Effect in Graphene Lattice Deformation as Gauge Fields Summary MAGNETISM OF NANOGraphene Introduction Theoretical Background of Magnetism in NanoGraphene and Graphene Edges Experimental Approach to Magnetism of NanoGraphene Magnetic Phenomena Arising in the Interaction with Guest Molecules in NanoGraphene-Based Nanoporous Carbon Summary PHYSICS OF ELECTRICAL NOISE IN Graphene Introduction Flicker Noise or "1/f ' Noise in Electrical Conductivity of Graphene Noise in Quantum Transport in Graphene at Low Temperature Quantum-Confined Graphene Conclusions and Outlook SUSPENDED Graphene DEVICES FOR NANOELECTROMECHANICS AND FOR THE STUDY OF QUANTUM HALL EFFECT Introduction Quantum Hall Effect in Graphene Fabrication of Suspended Graphene Devices Nanoelectromechanics Using Suspended Graphene Devices Using Suspended Graphene NEMS Devices to Measure Thermal Expansion of Graphene High-Mobility Suspended Graphene Devices to Study Quantum Hall Effect ELECTRONIC AND MAGNETIC PROPERTIES OF PATTERNED NANORIBBONS: A DETAILED COMPUTATIONAL STUDY Introduction Experimental Results Theory of GNRs Hydrogenation at the Edges Novel Properties Outlook STONE-WALES DEFECTS IN Graphene AND RELATED TWO-DIMENSIONAL NANOMATERIALS Introduction Computational Methods Graphene: Stone-Wales (SW) Defects C1-x(BN)x/2: C-BN Interfaces Two-Dimensional MoS2 and MoSe2 Summary Graphene AND Graphene-OXIDE-BASED MATERIALS FOR ELECTROCHEMICAL ENERGY SYSTEMS Introduction Graphene-Based Materials for Fuel Cells Graphene-Based Supercapacitors Graphene in Batteries Conclusions and Future Perspectives HETEROGENEOUS CATALYSIS BY METAL NANOPARTICLES SUPPORTED ON Graphene Introduction Synthesis of Graphene and Metal Nanoparticles Supported on Graphene Pd/Graphene Heterogeneous Catalysts for Carbon-Carbon Cross-Coupling Reactions CO Oxidation by Transition-Metal/Metal-Oxide Nanoparticles Supported on Graphene Conclusions and Outlook GrapheneS IN SUPRAMOLECULAR GELS AND IN BIOLOGICAL SYSTEMS Introduction Toward the Gelation of GO Polymer-Assisted Formation of Multifunctional Graphene Gels Graphene Aerogels Hydrogel and Organogel as the Host for the Incorporation of Graphene Biological Applications Involving Graphene Conclusions and Future Directions BIOMEDICAL APPLICATIONS OF Graphene: OPPORTUNITIES AND CHALLENGES Introduction Summary of Physical and Chemical Properties of Graphene Cellular Uptake, Biodistribution, and Clearance Toxicity of Graphene Mitigation of Toxicity by Surface Modifications In vivo Toxicity Potential Application Areas: Opportunities Conclusions INDEX
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Some novel attributes of Graphene
Journal of Physical Chemistry Letters, 2010Co-Authors: C. N. R. Rao, Rakesh Voggu, Anoop Kumar Sood, K. S. SubrahmanyamAbstract:Graphene has generated great sensation due to its amazing proper- ties, and extensive research is being pursued on single- as well as bi- and few-layer Graphenes. In this Perspective, we highlight some aspects of Graphene synthesis, surface, magnetic, and mechanical properties, as well as effects of doping and indicate a few useful directions for future research.
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A study of the synthetic methods and properties of Graphenes
Science and Technology of Advanced Materials, 2010Co-Authors: C. N. R. Rao, H. S.s.ramakrishna Matte, B. Abdulhakeem, Anupama Ghosh, A. Govindaraj, K. S. Subrahmanyam, Barun Das, Prashant Kumar, Dattatray J. LateAbstract:Graphenes with varying number of layers can be synthesized by using different strategies. Thus, single-layer Graphene is prepared by micromechanical cleavage, reduction of single-layer Graphene oxide, chemical vapor deposition and other methods. Few-layer Graphenes are synthesized by conversion of nanodiamond, arc discharge of graphite and other methods. In this article, we briefly overview the various synthetic methods and the surface, magnetic and electrical properties of the produced Graphenes. Few-layer Graphenes exhibit ferromagnetic features along with antiferromagnetic properties, independent of the method of preparation. Aside from the data on electrical conductivity of Graphenes and Graphene-polymer composites, we also present the field-effect transistor characteristics of Graphenes. Only single-layer reduced Graphene oxide exhibits ambipolar properties. The interaction of electron donor and acceptor molecules with few-layer Graphene samples is examined in detail.
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Graphene: The new two-dimensional nanomaterial
Angewandte Chemie - International Edition, 2009Co-Authors: C. N. R. Rao, Anoop Kumar Sood, K. S. Subrahmanyam, A. GovindarajAbstract:Every few years, a new material with unique properties emerges and fascinates the scientific community, typical recent examples being high-temperature superconductors and carbon nanotubes. Graphene is the latest sensation with unusual properties, such as half-integer quantum Hall effect and ballistic electron transport. This two-dimensional material which is the parent of all graphitic carbon forms is strictly expected to comprise a single layer, but there is considerable interest in investigating two-layer and few-layer Graphenes as well. Synthesis and characterization of Graphenes pose challenges, but there has been considerable progress in the last year or so. Herein, we present the status of Graphene research which includes aspects related to synthesis, characterization, structure, and properties.
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Graphene, the new nanocarbon
Journal of Materials Chemistry, 2009Co-Authors: C. N. R. Rao, Kanishka Biswas, K. S. Subrahmanyam, A. GovindarajAbstract:Graphene is a fascinating new nanocarbon possessing, single-, bi- or few- ([less-than-or-equal] ten) layers of carbon atoms forming six-membered rings. Different types of Graphene have been investigated by X-ray diffraction, atomic force microscopy, transmission electron microscopy, scanning tunneling microscopy and Raman spectroscopy. The extraordinary electronic properties of single-and bi-layer Graphenes are indeed most unique and unexpected. Other properties of Graphene such as gas adsorption characteristics, magnetic and electrochemical properties and the effects of doping by electrons and holes are equally noteworthy. Interestingly, molecular charge-transfer also markedly affects the electronic structure and properties of Graphene. Many aspects of Graphene are yet to be explored, including synthetic strategies which can yield sufficient quantities of Graphene with the desired number of layers.
František Karlický - One of the best experts on this subject based on the ideXlab platform.
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Halogenated Graphenes: rapidly growing family of Graphene derivatives.
ACS Nano, 2013Co-Authors: František Karlický, Michal Otyepka, K. K. R. Datta, Radek ZbořilAbstract:Graphene derivatives containing covalently bound halogens (Graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp2 carbons changes the hybridization state to sp3, which has a principal impact on electronic properties and local structure of the material. The fully fluorinated Graphene derivative, fluoroGraphene (Graphene fluoride, C1F1), is the thinnest insulator and the only stable stoichiometric Graphene halide (C1X1). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluoroGraphene and other partially fluorinated, chlorinated, and brominated Graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of Graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated Graphenes, iodine-doped Graphene, and mixed Graphene halides. Finally, patterned halogenati...
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Halogenated Graphenes: Rapidly growing family of Graphene derivatives
ACS Nano, 2013Co-Authors: František Karlický, Kasibhatta Kumara Ramanatha Datta, Michal Otyepka, Radek ZbořilAbstract:Graphene derivatives containing covalently bound halogens (Graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp(2) carbons changes the hybridization state to sp(3), which has a principal impact on electronic properties and local structure of the material. The fully fluorinated Graphene derivative, fluoroGraphene (Graphene fluoride, C1F1), is the thinnest insulator and the only stable stoichiometric Graphene halide (C1X1). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluoroGraphene and other partially fluorinated, chlorinated, and brominated Graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of Graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated Graphenes, iodine-doped Graphene, and mixed Graphene halides. Finally, patterned halogenation is presented as an interesting approach for generating materials with applications in the field of Graphene-based electronic devices.
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Graphene fluoride: A stable stoichiometric Graphene derivative and its chemical conversion to Graphene
Small, 2010Co-Authors: Radek Zbořil, Athanasios B. Bourlinos, František Karlický, Theodore A. Steriotis, Dalibor Jančík, Christos Trapalis, Athanasios K. Stubos, Klára Šafářová, Vasilios Georgakilas, Michal OtyepkaAbstract:Stoichoimetric Graphene fluoride monolayers are obtained in a single step by the liquid-phase exfoliation of graphite fluoride with sulfolane. Comparative quantum-mechanical calculations reveal that Graphene fluoride is the most thermodynamically stable of five studied hypothetical Graphene derivatives; graphane, Graphene fluoride, bromide, chloride, and iodide. The Graphene fluoride is transformed into Graphene via Graphene iodide, a spontaneously decomposing intermediate. The calculated bandgaps of Graphene halides vary from zero for Graphene bromide to 3.1 eV for Graphene fluoride. It is possible to design the electronic properties of such two-dimensional crystals.