ultra small single walled carbon nanotubes and their novel properties

... (2007) 2:447–449 Table Calculated total energy of singlet and triplet state for boron and nitrogen doped single wall zig-zag and armchair carbon nanotubes Formula Type C68B2 Armchair Method Total ... energy between the singlet and doublet states The + sign means the triplet state has lower energy than the singlet state Fig (a) Optimized structure of C68B2 armchair single walled carbon nanotube ... C68B2 single walled carbon nanotube Methods and Results The structures at minimum energy of zig-zag (7,0) and armchair (5,5) tubes are obtained using the Hartree Fock method employing a 6-31G and...

Ngày tải lên: 22/06/2014, 18:20

... and desorption of ozone on the exterior of a (5,5) single- walled carbon nanotube, Chem Phys Lett 398 (2004) 297–303 N.I Kovtyukhova, T.E Mallouk, L Pan, E.C Dickey, Individual single- walled nanotubes ... of ozone oxidation on single- walled carbon nanotubes, J Phys Chem B 110 (2006) 7113–7118 J Li, Y Lu, Q Ye, M Cinke, J Han, M Meyyappan, Carbon nanotube sensors for gas and organic vapor detection, ... E.C Dickey, P.C Eklund, Debundling and dissolution of single- walled carbon nanotubes in amide solvents, J Am Chem Soc 126 (2004) 6095–6105 N Sano, F Ohtsuki, Carbon nanohorn sensor to detect ozone...

Ngày tải lên: 19/03/2014, 16:47

... spectroscopy applied to single- walled carbon nanotubes Chem Phys Lett 2005, 410:136 Hartschuh A, Qian H, Meixner AJ, Anderson AJ, Novotny L: Nanoscale optical imaging of single- walled carbon nanotubes J ... AJ, Anderson N, Novotny L: Nanoscale Optical Imaging of Excitons in Single- Walled Carbon Nanotubes Nano Lett 2005, 5:2310 11 Roy D, Williams C: High resolution Raman imaging of single wall carbon ... apex or in the gap between the tip and the sample and therefore small shifts of the plasmon resonance can occur These induce small shifts in the RBM frequencies and therefore tubes with slightly...

Ngày tải lên: 21/06/2014, 05:20

... *1580 cm-1 corresponding to sp2-hybridized carbon and a D band at *1346 cm-1 originating from disordered carbon [17, 18] In addition to the D band, the D0 band as a shoulder of the Nanoscale Res ... those D band, D0 band and G band peaks changed only slightly Additional Raman peaks from the ZnO shells appeared; the relatively strong peaks at 427 and 567 cm-1 correspond to Ehigh and A1 (LO) ... MWCNTs (Fig curve a) shows a strong D band, indicating the existence of defects on the tube wall Compared to MWCNTs, the surfaces of the single- walled carbon nanotubes (SWCNTs) are known to have...

Ngày tải lên: 21/06/2014, 08:20

... SWCNTs are formed and there are only poorly multi -walled carbon nanotubes (MWCNTs) and organized carbon in the sample The relatively high intensity of the D band relative to G band (ID/IG = 0.72) ... region (100–300 cm-1), two outstanding RBM bands are presented According to the formula [14], the peaks at 147 and 169 cm-1 correspond to the SWCNTs with diameter of 1.59 and 1.38 nm, respectively ... product consists of single and bundle SWCNTs with even diameters The intensity ratio becomes lower with ID/IG = 0.32 and the TEM shows that there are only a few amorphous carbons in the SWCNTs...

Ngày tải lên: 22/06/2014, 00:20

... 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 (MWCNTs) [14–18] ... MWCNFs, SWCNTs consist of single graphene layer rolled into tubes SWCNTs are vulnerable to be damaged on their frameworks and thus, they will loose their outstanding properties Thus, as-received ... mechanical stirrer, and nitrogen inlet and outlet, custom synthesized TMPBA (0.5 g, 1.96 mmol), and PPA treated SWCNTs (0.5 g, 41.6 mmol), and PPA (83% assay, 20 g) were charged and the mixture was...

Ngày tải lên: 22/06/2014, 00:20

... the MWNT and the presence of the graphitized layer between the nanotubes and carbon paper in Sample C The absence of the graphitized layer between the MWNT and carbon paper in samples B and D adversely ... coated over carbon paper with and without graphitic layer (sample A and sample B) and that of purified MWNT spin coated over carbon paper with and without graphitic layer (sample C and sample D), ... coated over carbon paper with and without graphitic layer (sample A and sample B) and that of purified MWNT spin coated over carbon paper with and without graphitic layer (sample C and sample D)...

Ngày tải lên: 22/06/2014, 18:20

... natural gas [19] The hydrogen produced is free of carbon monoxide and the other products being tubular carbon Results obtained on the generation of carbon monoxide-free hydrogen during the CVD growth ... observed The carbon yield during the deposition has been calculated as described previously [17] and a dependence of the yield of carbon with the growth temperature has been plotted and shown in ... development and fabrication of microelectrodes in fuel cell technology and as hydrogen sensors Filling of hydrogen storage alloy nanowires inside CNTs prevents them from oxidation and hence results in their...

Ngày tải lên: 22/06/2014, 22:20

... Inselspital and University of Bern, Bern, Switzerland 4Department of Chemical Biology and Therapeutics, St Jude Children’s Research Hospital, Memphis, TN 38105, USA and School of Chemistry and Chemical ... carbon nanotube material: Aerosol release during the handling of unrefined single- walled carbon nanotube material Journal of Toxicology and Environmental Health-Part A 2004, 67:87-107 Kaiser ... interactions: how carbon nanotubes affect cell physiology? Nanomedicine 2009, 4:57-63 Ryman-Rasmussen JP, Tewksbury EW, Moss OR, Cesta MF, Wong BA, Bonner JC: Inhaled Multiwalled Carbon Nanotubes Potentiate...

Ngày tải lên: 11/08/2014, 00:22

... of single- wall carbon nanotubes with endothelial cells Nanomed 2010, 6:277-288 11 Jin H, Heller DA, Sharma R, Strano MS: Size-dependent cellular uptake and expulsion of single- walled carbon nanotubes: ... Toxicity studies of carbon nanotubes Adv Exp Med Biol 2007, 620:181-204 Kaiser JP, Wick P, Manser P, Spohn P, Bruinink A: Single walled carbon nanotubes (SWCNT) affect cell physiology and cell architecture ... provided SWCNTS and helped design and analyze FLIM and Raman experiments KND provided cells, reagents and rDNA and helped design and analyze cellular experiments All authors have read and approved...

Ngày tải lên: 11/08/2014, 08:20

... (MWCNTs-f-PANI) and noble metal (Au and Ag) nanoparticles Firstly, MWCNTs-f-PANI was prepared For this we modified the carbon nanotubes (MWCNTs-COCl) with DABSA via amide linkage, and subsequently ... CNTs (Fig 1b) and MWCNTs-f-PANI (Fig 1d and e) also clearly indicates that the carbon nanotubes were encapsulated by ordered PANI chains In addition, it can be clearly seen from Figs and that the ... initially dispersed in ethanol by ultrasonication for Afterwards, a drop of the suspension was transferred onto a carbon coated copper grid and mounted on the microscope, and the micrographs were recorded...

Ngày tải lên: 05/05/2014, 15:26

... optical properties of the carbon nanotubes Indeed, Hanson has predicted that the presence of a plasmonic nanoparticle on a carbon nanotube wall affects the electric field and current on the carbon ... Steiner M, Novotny L, Krauss TD: Single carbon nanotube optical spectroscopy ChemPhysChem 2005, 6:1-6 16 Weisman RB: Optical spectroscopy of single- walled carbon nanotubes Department of Chemistry, ... metallic, semi-metallic, and semiconducting structures Fine structure has been documented in isolated carbon nanotubes or dispersions of SWCNT [15,16] When the carbon nanotubes are not dispersed,...

Ngày tải lên: 20/06/2014, 22:20

... isolated 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 ... addition to these outstanding properties, the recent developments on graphene synthesis routes and on -2- the understanding of their unique properties have prompted the development and study of graphene ... values reported for single- walled carbon nanotube bundles [9], high electrical conductivity of up to 6,000 S/cm [10], and superior mechanical properties with Young's modulus of TPa and ultimate strength...

Ngày tải lên: 20/06/2014, 23:20

... approximately 1,370 and 1,580 cm -1 are related to carbon, which are designated in terms of D and G bands These peaks are in good correspondence with the Raman spectra of the amorphous carbon reported ... demonstrated the synthesis of carbon- coated ZnWO nanorods with a one-dimensional core/shell structure using a simple hydrothermal route and subsequent carbon coating, and their enhanced Li-storage ... ZW and C-ZW nanorods (b) Magnified Raman spectra showing D and G bands by carbon coating in C-ZW nanorods (By HW Shim et al.) Figure Representative TEM images of C-ZW nanorods (a, b) Low and...

Ngày tải lên: 20/06/2014, 23:20

... contacts The low ON/OFF ratio is due to the small SWCNT bandgap and can be enhanced by selecting a semiconducting SWCNT with smaller diameter and large bandgap In our previous work [15, 17], we ... made of Pd/Nb and the doped Si substrate is used as back-gate electrode small channel bandgap At room temperature (blue triangle), the CNFET exhibits a small ON/OFF current ratio (B10) and a low ... contact resistance and large ON/OFF ratio, with the same fabrication process used for the samples discussed here Because we use nanotubes with a small bandgap, we can test memory device properties for...

Ngày tải lên: 21/06/2014, 08:20

... functionalize multi -walled carbon nanotubes (MWCNTs) with minor negative consequences in nanotube structure [24] In the process, high incident energy hydrogen and oxygen cations generated and extracted ... pristine MWCNTs and the five chemical species: (1) graphite; (2) sp3 carbons; (3) hydroxyl groups; (4) carbonyl groups; and (5) carboxyl groups Fig XPS survey spectra of the pristine MWCNTs and the ECRplasma-treated ... pristine and the plasma-treated MWCNTs are presented in Fig Two characteristic peaks are observed and attributed to the D and G bands The spectra have been normalized with respect to the G band for...

Ngày tải lên: 22/06/2014, 01:20

... BC2N nanotubes possess nonsymmorphic line groups, just like carbon nanotubes [8] and boron nitride nanotubes [11] Contrary to carbon and boron nitride nanotubes, armchair and zigzag BC2N nanotubes ... BC2N nanotubes a ZZ-2 and b AC-2 z is a glide plane spectra between 100 and 300 cm-1 should be attributed to E1g and A1g modes [22] Conclusions In summary, the symmetry properties of BC2N nanotubes ... nanotubes have 19 Raman- and 10 IR-active phonon modes; all ZZ-2, AC-2, and other chiral BC2N nanotubes have 33 Raman- and 21 IR-active phonon modes It is noticed that the numbers of Raman- and...

Ngày tải lên: 22/06/2014, 01:20

... defects become fewer and fewer When the temperature is lower than 72 K, the DWCNT becomes electrically unstable after VG sweeping, and the change in conductance is random and unpredictable Furthermore, ... states, and can be disturbed by the VG and thermal activation The two-dimensional dI/dV plot as a function of VD and VG for the sample No (Fig 3c) indicates that the positions of the dI/dV dips and ... synchronously The electrical transport properties of DWCNTs characterized by multi-stable conductance states might originate from their larruping microstructures: small diameter and two layers It is said...

Ngày tải lên: 22/06/2014, 01:20

... structure and electronic properties of single- walled carbon nanotubes Nature, 391(6662), 62–64 Santos, C.V., Hernandez, A.L.M., Fisher, F.T., Ruoff, R & Castano, V.M (2003) Improvement of thermal and ... weak and broad band around 3000 cm–1 is assigned to the N-H stretching mode Figures 3(a) and (b) show PANI/MWCNTs and PANI/MWCNTs-MnO2, respectively There were clear differences between these and ... PANI/MWCNTs and PANI/MWCNTs-MnO2 were measured according to the standard four-point probe method The conductivity of the samples were measured and calculated to be 38.34 Scm–1, 50.56 Scm–1 and 57.74...

Ngày tải lên: 07/08/2014, 14:20

... peptide-wrapped singlewalled carbon nanotubes Small 2005, 1:820-823 Karajanagi SS, Yang H, Asuri P, Sellitto E, Dordick JS, Kane RS: Protein-Assisted Solubilization of Single- Walled Carbon Nanotubes ... on isolated single wall carbon nanotubes Carbon 2002, 40:2043-2061 Resasco DE, Herrera JE: Structural characterization of singlewalled carbon nanotubes Encyclopedia of Nanoscience and Nanotechnology ... Bioelectrochemical single- walled carbon nanotubes Journal of the American Chemical Society 2002, 124:12664-12665 Lin Y, Allard LF, Sun YP: Protein-Affinity of Single- Walled Carbon Nanotubes in Water...

Ngày tải lên: 11/08/2014, 00:22