electronic properties of carbon nanotubes experimental results

... physical properties of the nanotubes The symmetry groups for carbon nanotubes can be either symmorphic [such as armchair (n,n)and zigzag Physics of carbon nanotubes 29 Table Parameters of carbon nanotubes ... progress in research on carbon nanotubes and related materials 'The birth of the field of carbon nanotubes is marked by the publication by Iijima of the observation of multi-walled nanotubes with outer ... implications of symmetry on the vibrational and electronic structure of ID carbon nanotube systems are considered The corresponding properties of double-wall nanotubes and arrays of nanotubes are...

Ngày tải lên: 05/03/2014, 15:21

... physical properties of the nanotubes The symmetry groups for carbon nanotubes can be either symmorphic [such as armchair (n,n)and zigzag Physics of carbon nanotubes 29 Table Parameters of carbon nanotubes ... progress in research on carbon nanotubes and related materials 'The birth of the field of carbon nanotubes is marked by the publication by Iijima of the observation of multi-walled nanotubes with outer ... implications of symmetry on the vibrational and electronic structure of ID carbon nanotube systems are considered The corresponding properties of double-wall nanotubes and arrays of nanotubes are...

Ngày tải lên: 27/06/2014, 17:20

... physical properties of the nanotubes The symmetry groups for carbon nanotubes can be either symmorphic [such as armchair (n,n)and zigzag Physics of carbon nanotubes 29 Table Parameters of carbon nanotubes ... progress in research on carbon nanotubes and related materials 'The birth of the field of carbon nanotubes is marked by the publication by Iijima of the observation of multi-walled nanotubes with outer ... implications of symmetry on the vibrational and electronic structure of ID carbon nanotube systems are considered The corresponding properties of double-wall nanotubes and arrays of nanotubes are...

Ngày tải lên: 27/06/2014, 17:20

... sensor response, and times of adsorption/desorption of screenprinted and dip-coated films sensing a flux of 150 mL of N2 with a charge of 1% NH3 Material Fig Optical properties of: (a) dip-coated films, ... size of titania symbols are representative of the lack (white) or abundance (yellow) of Ti3+ states and of the crystallite size obtained by XRD; the size of the arrows illustrate the magnitude of ... the identification of small changes in the patterns of the composite films; the narrower and more symmetric shape of the MWCNT peak at 2Â = 26◦ indicates the lost of amorphous carbon after functionalization...

Ngày tải lên: 20/03/2014, 13:07

... top It can also be stated that the edges of the Figure STM images of the edges of the graphene islands (a) 23 × 23 nm2 STM image of a monolayer on top of the (3 × 3) SiCreconstructed surface This ... 20 21 22 23 24 Page of atmospheric pressure graphitization of silicon carbide Nat Mater 2009, 8:203 Kim S, Ihm J, Choi HJ, Son YW: Origin of anomalous electronic structures of epitaxial graphene ... http://www.nanoscalereslett.com/content/6/1/171 Page of (a) (b) (c) (d) Figure STM images of a 6H-SiC(000-1) sample after graphitization (same sample as in figure 1) (a) 300 × 300 nm2 STM image of few layers of graphene grown...

Ngày tải lên: 21/06/2014, 05:20

... thermoelectric properties of a series of zigzag and chiral carbon nanotubes which exhibit interesting diameter and chirality dependence Our calculated results indicate that these carbon nanotubes ... dynamics of singlewalled carbon nanotubes Phys Rev B 2003, 67:045413 33 Esfarjani K, Zebarjadi M, Kawazoe Y: Thermoelectric properties of a nanocontact made of two-capped single-wall carbon nanotubes ... Thermal conductivity of carbon nanotubes Nanotechnology 2000, 11:65-69 30 Padgett CW, Brenner DW: Influence of chemisorption on the thermal conductivity of single-wall carbon nanotubes Nano Lett...

Ngày tải lên: 21/06/2014, 17:20

... properties of carbon nanotubes 1.1.3 Applications of carbon nanotubes 1.2 Motivation 1.3 Objective and scope of work 11 1.4 Layout of the thesis 13 CHAPTER 2: LITERATURE REVIEW 2.1 Buckling of ... achiral carbon nanotubes The latter comprises of both zigzag and armchair carbon nanotubes This categorization is done based on the orientation of carbon- carbon (C-C) bonds Orientation of C-C ... bonds where each carbon atom is bonded to other carbon atoms 1.1.2 Mechanical properties of carbon nanotubes Carbon nanotube is known to possess superior mechanical properties These properties have...

Ngày tải lên: 09/09/2015, 18:54

... Background 1.2 Carbon Nanotubes 1.2.1 Discovery of Carbon Nanotubes 1.2.2 Bonding Structures of Carbon Nanotubes 1.2.3 Properties of Carbon Nanotubes 1.2.4 Applications of Carbon Nanotubes 2 13 ... outer shell of the CNTs, whatever type of electronic properties may be [32, 33] Field Emission Properties of Carbon Nanotubes It is known that a CNT is a very thin filament-like carbon molecule ... 49 CHAPTER NANOTUBES SYNTHESIS OF VERTICALLY-ALIGNED CARBON 51 4.1 Introduction 51 4.2 Experimental Details 54 4.3 Results and Discussion 4.3.1 Characterization of the As-Grown Carbon Nanotubes...

Ngày tải lên: 11/09/2015, 10:17

... space charge effects, overheating of the emitter tips or the low concentration of the carriers in the tips, conduction band of semiconductors [15-17] FE properties of semiconductors could on 17] ... Influencing Parameters of Field Emission Based on the above review of the F-N theory and the literature on FE from semiconductors, it is obvious that the FE properties of materials are essentially ... FE performances of emitters Threshold voltage, defined as the anode voltage where an emission current of 10-9 A was observed, is an essential index to evaluate the FE properties of emitters [35]...

Ngày tải lên: 11/09/2015, 10:17

... spectrum of a mixture of elements is approximately the sum of the peaks of the individual constituents Generally, identification of chemical states can be made from exact measurements of peak ... representing the order of diffraction, λ is the wavelength, d is the interplanar spacing of the reflecting (diffracting) plane, and θ is the angle of the incidence and of the diffraction of the radiation ... outermost levels of atoms - the valence levels The advantage of using such a UV radiation over X-rays is the very narrow line width of the radiation and the availability of high flux of photons from...

Ngày tải lên: 11/09/2015, 10:17

... covered with amorphous carbon, which is the product of the thermal deposition of hydrocarbon [3] 52    Chapter Synthesis of Vertically-Aligned Carbon Nanotubes In terms of other CNT growth approaches, ... Schematic setup of the PECVD system used 55    Chapter Synthesis of Vertically-Aligned Carbon Nanotubes 4.3 Results and Discussion 4.3.1 Characterization of the As-Grown Carbon Nanotubes Fig 4.2 ... the hollow part of   Fig 4.4 TEM images of the as-grown CNTs obtained with Fe catalyst 58    Chapter Synthesis of Vertically-Aligned Carbon Nanotubes the nanotube that a few layers of graphene sheets...

Ngày tải lên: 11/09/2015, 10:18

... of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures 6.3.4 FE Performance of the Composite Emitters with Varied Thicknesses of Coating Films The FE properties ... the binding energy (BE) of 284.5 and 285.2 eV confirm a high sp3 content of 126 Chapter Field Emission Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures ... (eV) Fig 6.5 Carbon 1s core level XPS spectrum confirms high sp3 content of the DLC films 127 Chapter Field Emission Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell...

Ngày tải lên: 11/09/2015, 10:18

... Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures of the pristine CNTs Hence, it is reasonable to assume that the coated tips of these nanotubes ... flat and the average diameter of these nanotubes is comparable to that 136 Chapter Field Emission Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures ... Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures with the increase of ambient temperature during emission process, the work function of the...

Ngày tải lên: 11/09/2015, 10:18

... Emission Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures 6.4.2 FE Properties of the Hydrogenated Composite Emitters The FE J-E curves of the pristine ... Chapter Field Emission Study of Hydrogenated Tetrahedral Amorphous Carbon Coated Carbon Nanotubes Core-Shell Nanostructures Fig 6.15 Carbon 1s core level XPS spectra of the (a) 50 nm ta C coated ... Carbon Coated Carbon Nanotubes Core-Shell Nanostructures performance of the emitters and there exists an optimum thickness of the ta-C coating film, i.e., 50 nm in this case With the change of...

Ngày tải lên: 11/09/2015, 10:18

... the FE properties of the pristine CNTs Results showed that the FE properties of the CNTs would be affected both by the thickness of the ta-C coating films and by the treatment duration of the ... Emission Properties of Hydrogen Plasma Post-Treatment on Tetrahedral Amorphous Carbon Coated Carbon Nanotubes , IEEE International NanoElectronics Conference (INEC) 2010, City University of Hong ... characteristics of tetrahedral amorphous carbon coated carbon nanotubes Journal of Physical Chemistry C (Accepted) Jun Yu, Kuan He Choo, Lifang Niu, and Daniel H C Chua “Synthesis of three-dimensional...

Ngày tải lên: 11/09/2015, 10:18

... single wall carbon nanotubes Carbon 2002, 40:2043-2061 24 Deng F, Zheng QS, Wang LF: Effects of anisotropy, aspect ratio, and nonstraightness of carbon nanotubes on thermal conductivity of carbon ... final properties of the system Thus, we aimed at studying the effect of two types of carbon- based nanofillers, in particular, nanotubes and graphene sheets, on the thermal conductivity of an ... observed The results indicate that MWNTs are the most effective carbon nanofillers to improve the K of liquid resins Indeed, the K of the nanofluids gradually increased as a function of MWNT content,...

Ngày tải lên: 20/06/2014, 23:20

... important results have been obtained for BN and other noncarbon nanotubes as well BN nanotubes share the same sp2 structure of carbon nanotubes and thus many mechanical properties similarities exist Nanotubes ... oxygen sensitivity of electronic properties of carbon nanotubes, Science 287, 1801 (2000) [81] J Hone, M Whitney, C Piskoti and A Zettl, Thermal conductivity of single-walled carbon nanotubes, Phys ... giving rise to many kinds of new crystalline carbon phases [3] In the case of carbon nanotubes, existence of many kinds of nanotubes in various samples has also been confirmed experimentally using...

Ngày tải lên: 04/06/2014, 14:43

... energy of singlewalled carbon nanotubes Appl Phys Lett 1999, 16:2307-2309 Peigney A, Laurent C, Flahaut E, Bacsa RR, Rousset A: Specific surface area of carbon nanotubes and bundles of carbon nanotubes ... Physicochemical properties of CNTs Carbon nanotubes are a huge cylindrical large molecules consisting of a hexagonal arrangement of sp2 hybridized carbon atoms (C-C distance is about 1.4 Ǻ) The wall of CNTs ... applications of single walled carbon nanotubes Curr Med Chem 2010, 17:10-24 Ito Y, Venkatesan N, Hirako N, Sugioka N, Takada K: Effect of fiber length of carbon nanotubes on the absorption of erythropoietin...

Ngày tải lên: 20/06/2014, 22:20

... polymerization of phenoxybenzoic acids [11] and functionalization of closely related carbon materials such as vapor-grown multi-walled carbon nanofibers (MWCNFs) [12, 13] and multi-walled carbon nanotubes ... Without purification, most of the as-prepared SWCNTs contain approximately 60–70 wt% of impurities such as carbonaceous fragments, amorphous carbons, and small amount of graphite and metal catalysts ... 1550–1600 cm-1 region of spectrum is due to the tangential C–C stretching of SWCNT carbon atoms [25] The ID/IG value of the TMPBA-g-SWCNT was 1.3, which was much lower than 5.0 of the PPA treated...

Ngày tải lên: 22/06/2014, 00:20