Carbon nanotubes metal free

For metallic single-wall carbon nanotubes the free-electron model of electronic structure with finite thickness of the conducting shell is proposed. The band stmcture calculations in the frame of this model of armchair (n,n) nanotubes (for n = 5-10) show essential similarity with tight-binding description. 

Metal-Free Catalysis by Oxygen-Containing Carbon Nanotubes... 

Yu, J. Yang, B. Cheng, B., Noble-metal-free carbon nanotube-Cd01Zn09S composites for high visible-light photocatalytic H2-production performance. Nanoscale 2012,4 2670-2677. 

Fig. 1.1 Idealized representation of different structures of defect-free and opened carbon nanotubes (a) concentric MWCNT (b) metallic armchair [10,10] SWCNT (c) helical...

Sen, R. Govindaraj, A. Rao, C. N. R. Metal-filled and hollow carbon nanotubes obtained by the decomposition of metal containing free precursor molecules. Chem. Mater. 1997 9. 207B. 

A large free volume is available inside the carbon nanotubes, which has been filled with various metals and gases. The filled carbon nanotubes have different physical... 

It occurs catalytically on the surface of Fe nanoparticles grown from Fe(CO)5. Also, the conventional synthesis of nanotubes by catalytic CVD from acetylene or methane can be formally considered as redox reaction. Nevertheless, the electrochemical model of carbonization (Sections 4.1.1 and 4.1.2) is hardly applicable for CVD and HiPco, since the nanotubes grow on the catalyst particle by apposition from the gas phase, and not from the barrier film (Figure 4.1). The yield and quality of electrochemically made nanotubes are usually not competitive to those of catalytic processes in carbon arc, laser ablation, CVD and HiPco. However, this methodology demonstrated that nanotubes (and also fullerenes and onions (Section 4.3)) can be prepared by soft chemistry" at room or sub-room temperatures [4,5,101]. Secondly, some electrochemical syntheses of nanotubes do not require a catalyst [4,5,95-98,100,101]. This might be attractive if high-purity, metal-free tubes are required. 

ELECTRONIC STRUCTURE OF METALLIC SINGLE-WALL CARBON NANOTUBES TIGHT-BINDING VERSUS FREE-ELECTRON APPROXIMATION... 

Density functional theory is a successful approach for the description of ground-state properties of metals, semiconductors, and insulators. It also has become an attractive method to calculate complex materials, such as proteins and carbon nanotubes. For example, DFT calculation has been used to compute anion-binding properties of 2,6-diamidopyridine dipyrromethane hybrid macrocycles (18), to predict drug resistance of HIV-1 reverse transcriptase to nevirapine through point mutations (19), and to analyze the 32-adrenergic G protein-coupled receptor (20). A free DFT software program also is available... 

In this experiment the metal-free carbon nanotubes acted directly as a support and active phase for the liquid-phase ODH of dihydroanthracene to anthracene at low temperature. The results are compared with those obtained on other catalysts. Oxidative dehydrogenation of dihydroanthracene in the liquid-phase was carried out over different CNT-based materials. The results are presented in Table 7.3. The test was also performed on an exfoliated graphite material for comparison. The results clearly showed that the reaction was chemically selective whatever... 

Aitola, K., Borghei, M., Kaskela, A., Kemppainen, E., Nasibulin, A.G., Kauppinen, E.I., Lund, P.D., Ruiz,V., Halme, 2012. Flexible metal-free counter electrode for dye solar celk based on conductive polymer and carbon nanotubes. J. Electroanal. Chem. 683,70-74. 

Huang S, Cai Q, Chen J, Qian Y, Zhang L. Metal-catalyst-free growth of single-waUed carbon nanotubes on substrates. J Am Chem Soc 2009 131 2094-5. 

Wang S, Yu D, Dai L. Polyelectrolyte functionalized carbon nanotubes as efficient metal-free electrocatalysts for oxygen reduction. / Am Chem Soc 2011 133(14) 5182-5. 

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