Details of the purification and analysis of the physicochemical properties of the singlewalled carbon nanotubes used in this article. We report a theoretical study on the electronic structures and photoassisted transport properties of three types of impuritydoped carbon nanotubes. Interest in the study of non carbon nanotubes is due to the possibility of their use as catalysts, sensors, and elements of electronic devices. Pdf structures of the socalled supercarbon nanotubes are proposed. The final experiment we will describe, the effect of magnetic impurities on the electronic structure of swnts, is important for a number of reasons. We present a framework to analyze these variations by quantifying the dispersion. In the case of solvent with a withdrawing group, electrons were extracted mainly from metallic swcnts, whereas small charge transfer was also observed in. Electronic and structural properties of multiwall carbon. Box 43, fi00014 helsinki, finland 2empa swiss federal laboratories for materials testing and. Structure based carbon nanotube sorting by sequencedependent dna assembly. This paper presents the results of combined investigation of the chemical bond formation in fluorinated multiwalled carbon nanotubes mwcnts with different fluorine contents 1055 wt % and reference compounds highly oriented pyrolytic graphite. The structure of an ideal infinitely long singlewalled carbon nanotube is that of a regular hexagonal lattice drawn on an infinite cylindrical surface, whose vertices are the positions of the carbon atoms.
Pdf electronic structure of pd nanoparticles on carbon. Structure and electron charge density distribution contour plots of openended singlewall carbon nanotubes with 6,6 size. Electronic structure of deformed carbon nanotubes varies widely depending on their chirality and deformation mode. Pdf accchemres effect of covalent chemistry on the. Krasheninnikov1,4 1materials physics division, university of helsinki, p. Electronic structure and chemical reactivity of carbon. First, the study reconfirms all the stm results on ideal carbon nanotubes to date. Conformation and electronic structure of dna in carbon. Carbon nanotubes cnts are amongst the most explored onedimensional nanostructures and have attracted tremendous interest from fundamental science and technological perspectives. We performed low temperature photoluminescence pl studies on individual oxygendoped singlewalled carbon nanotubes swcnts and correlated our observations to electronic structure simulations. Our experiment reveals multiple sharp asymmetric emission peaks at energies 50300 mev redshifted from that of the e 11 bright exciton peak. Previous stm studies of multiwalled nanotubes 6,7,8,9 and singlewalled nanotubes swnts 10 have provided indications of differing structures and diameterdependent electronic. Electronic structures of carbon nanotubes each carbon atom in the hexagonal lattice on a 2d graphene sheet possesses six valent electrons, among which are three 2sp2 electrons and one 2p electron.
Atrazhev resear ch institute of structural graphite materials, elektr odnaya ul. Pdf the electrical properties of various forms of carbon nanotubes are presented with particular emphasis placed on individual multiwall and. Pdf electronic structure of carbon multilayer nanotubes. Electronic structure of carbon nanotubes interacting with cu and li atoms. All known preparative methods 24 lead to polydisperse materials of semiconducting, semimetallic and metallic electronic types. Modifying the electronic structure of semiconducting. Sorting carbon nanotubes by electronic structure using density differentiation. They can be thought of as a sheet of graphite a hexagonal lattice of carbon rolled into a cylinder. Currently, nanotubes are synthesized not only from carbon, but also from gold, platinum, palladium, and a wide range of other elements. Carbon nanotubes cnts encapsulated with copper chains have been investigated with quantum mechanics calculations, with an emphasis on the effects of copper on cnts electronic structure and the. Tight binding model to understand electronic structure. Pdf electronic structure of fluorinated multiwalled.
Electronic structure and localized states at carbon nanotube tips. Electronic structure of carbon nanotubes interacting with. The electronic band structure variations of singlewalled carbon nanotubes swcnts using huckletight binding approximation theory are studied. Size, shape, and low energy electronic structure of carbon nanotubes c. Carbon nanotubes exhibit several technologically important characteristics. Saito et al, imperial college press 1998 isbn 1860940935. Electronic properties of carbon nanotubes intechopen. The main hurdle to the widespread application of singlewalled carbon nanotubes is their manipulation according to electronic structure. Section 7 presents the theory of the phonon dispersion in nanotubes and raman spectroscopy. Electronic structure of atomically resolved carbon nanotubes. Imaging electronic structure of carbon nanotubes by voltagecontrast scanning electron microscopy.
Singlewall carbon nanotubes 1, 2 are ideally suited for electron transport experiments on single molecules because they have a very robust atomic and electronic structure and are sufficiently. According to the chirality indices, the related expressions for energy dispersion variations of these elements are derived and plotted for zigzag and chiral nanotubes. The electron charge density contour plots of the carbon nanotubes see fig. Although it is not physically accurate, these cylinders can best be visualized by imagining a sheet of graphite that has been rolled into a tube. Effects of surface functionalization on the electronic and. The carbon atoms in nanotubes are arranged in long, hollow cylinders. Carbon nanotubes can be thought of as graphitic sheets with a hexagonal lattice that have been wrapped up into a seamless cylinder. Electronic structure control of singlewalled carbon.
Electronic structure of copperdecorated carbon nanotubes. Electronic structure and chemical nature of oxygen dopant. The structure of a carbon nanotube is formed by a layer of carbon atoms that are bonded together in a hexagonal honeycomb mesh. Pdf electronic structure and quantum transport in carbon nanotubes. We discuss the use of helical symmetry for the electronic structure of these nanotubes, and the resulting trends we observe in both band gap and strain energy versus nanotube radius, using. Electronic structure of carbon multilayer nanotubes a. Atomic structure and electronic properties of single. A comparative study on carbon silicon doping effects on electronic structure and surface electrostatic potential of 6,0 boronnitride nanotube. First carbon nanotube single electron transistors operating at low temperature are demonstrated by groups at delft university and uc berkeley. Carbon nanotubes can be thought of as graphitic sheets with a hexagonal lattice. These onedimensional 1d graphene sheets rolled into a tubular form have been the target of many researchers around the world.
Size, shape, and low energy electronic structure of carbon nanotubes. Electronic and structural properties of carbon nanotubes. Carbon nanotubes carbon nanotubes, long, thin cylinders of carbon, were discovered in 1991 by sumio iijima. Electronic structure of achiral gold nanotubes sciencedirect. It is shown that singlewall carbon nanotubes support both localized and delocalized electronic excitations which is a direct consequence of their onedimensional structure. This book concentrates on the semiconductor physics of carbon nanotubes, it brings unique insight into the phenomena encountered in the electronic. Our experiment reveals multiple sharp asymmetric emission peaks at energies 50300 mev redshifted from that of the e11 bright exciton peak. Electronicstructuredependent bacterial cytotoxicity of. Electronic structure of pd nanoparticles on carbon nanotubes. Mele department of physics, laboratory for research on the structure of matter, university of pennsylvania, philadelphia, pennsylvania 19104 received 27 august 1996 a theory of the longwavelength lowenergy electronic structure of graphitederived nanotubules.
Pdf atomic structure and electronic properties of single. Electronic properties and applications of singlewalled. Fundamental electronic properties and applications of single. Electronic structure of carbon nanotubes request pdf. The individual hollow concentric graphitic nanotubes that comprise these fibers can be visualized as constructed from rolledup single sheets of graphite. Electronic structure of carbon nanotubes sciencedirect. Wondrous world of carbon nanotubes internet reference, m. Since the length of the carbon carbon bonds is fairly fixed, there are constraints on the diameter of the cylinder and the arrangement of the.
The chapter is organized according to the increasing levels of complexity found in nanotube electronics. Since their discovery in 1991,1 carbon nanotubes cnts are the subject of a growing interest due to their potential applications in nanoelectronic. This oneatom thick layer of carbon is called graphene, and it is wrapped in the shape of a cylinder and bonded together to form a carbon nanotube. Electronelectron correlations in carbon nanotubes nature. Since their discovery in 19911, the peculiar electronic. Pdf imaging electronic structure of carbon nanotubes by. Electronic structure of borondoped carbon nanotubes. Accchemres effect of covalent chemistry on the electronic structure and properties of carbon nanotubes and graphene. Carbon nanotubes 1 are predicted to be metallic or semiconducting depending on their diameter and the helicity of the arrangement of graphitic rings in their walls 2,3,4,5. Electronic structure of carbon nanotubes springerlink. Cnts are structures made of single walls single walled carbon nanotubes or swnts or are multi concentric multi walled carbon nanotubes or mwnts. The density functional theory within the kohnsham approach, the pseudopotential method, and sets of plane waves are using to compare the electronic structures of singlewall carbon nanotubes swcnt. Near edge xray absorption fine structure spectroscopy xray photoelectron spectroscopy density functional calculations finite difference method a b s t r a c t the highresolution near edge xray absorption fine structure spectroscopy and xray.
The three 2sp2 electrons form the three bonds in the plane of the graphene sheet, leaving an unsaturated. These are large macromolecules that are unique for their size, shape, and remarkable physical properties. Tailoring electronic structures of carbon nanotubes by. The electronic structure of graphite has important consequences for the conduction properties of carbon nanotubes. Harris, cambridge university press 1999 isbn 0521554462 physical properties of carbon nanotubes, r. Atomic structure and electronic properties of singlewalled carbon nanotubes article pdf available in nature 3916662. Furthermore, the investigation of disordered, intercalated nanotube samples provides information about the charge carrier scattering rate and effective mass. Albeit topologically simple, they exhibit a rich variety of intriguing electronic properties, such as metallic and semiconducting behaviour. This unusual view of carbon nanotubes allows us to merge the solid. Recent advances in the solutionphase dispersion 5, 6, along with spectroscopic. Electronic band structure of carbon nanotube superlattices from first. Section 8 surveys the mechanical properties of nanotubes. Atomic structure and electronic properties of singlewalled carbon. Sorting carbon nanotubes by electronic structure using.
Pdf geometric and electronic structure of carbon nanotube. Controlling the structure and properties of carbon nanotubes. These structures are built from single walled carbon nanotubes. Carbon nanotubes cnts, discovered in 1991, have been a subject of intensive research for a wide range of applications. Electronic structure of sidoped bn nanotubes using xray. Various electron donating and withdrawing groups in aromatic and aliphatic backbones of solvent have been introduced to tailor the electronic structures of singlewalled carbon nanotubes swcnts. The conformation and electronic structure of dna in singlewalled carbon nanotubes swcnt were studied by combining molecular dynamics and firstprinciples methods.
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