We report the growth of ultralong (>10 cm) multi-walled and single-walled carbon nanotubes such that the length is limited by the size of the furnace rather than by the termination of growth. The disturbance of microscale laminar flows results in disordered or shorter growth of carbon nanotubes. By downsizing reaction pipes, reaction gas flows are stabilized with low Reynolds numbers. In this w...

in this research, the effect of catalyst type on the cnts synthesis was investigated. the carbonnanotubes (cnts) were produced on stainless steel substrates and two of catalyst with differentcharacteristics by using thermal chemical vapor deposition (tcvd) method. the catalysts have theimportant role for the growth carbon nanotubes (cnts). acetylene gas (c2h2) diluted by nh3 wasused as the reac...

Polymeric composites with carbon nanotubes have still not explored the potential expected from the excellent mechanical properties of the carbon nanotubes and their large aspect ratio. Dispersion of the nanotubes within the polymeric matrix is difficult. SWCNTs agglomerates in bundles and a good dispersion of carbon nanotubes within the polymeric matrix is crucial in order to receive the optima...

The well-defined geometry, exceptional mechanical properties, and extraordinary electrical characteristics of carbon nanotubes qualify them for structuring nanoelectronic circuits, nanoelectromechanical systems, and nanorobotic systems. Relative displacements between the atomically smooth, nested shells in multiwalled carbon nanotubes can be used as robust nanoscale motion enabling mechanisms f...

single-walled carbon nanotubes (swnts) with high yield and quality were synthesized using chemical vapor deposition (cvd) over co-mo/ mgo nanocatalyst in a fluidized bed reactor. different parameters such as temperature, the ratio of hydrocarbon source to hydrogen, the flow rate of gas, growth time, the size of catalyst particles, heating rate, and the kind of hydrocarbon source were examined t...

Dense alignment of single-walled carbon nanotubes over a large area is demonstrated using a novel solution-shearing technique. A density of 150-200 single-walled carbon nanotubes per micro-meter is achieved with a current density of 10.08 μA μm(-1) at VDS = -1 V. The on-current density is improved by a factor of 45 over that of random-network single-walled carbon nanotubes.

The 2008 Kavli Prize in Nanoscience was awarded to Dr. Sumio Iijima for his contributions in the field of carbon nanotubes. Carbon nanotubes are molecular-scale wires with well-defined and atomically smooth surfaces that exhibit remarkable properties. Great progress has been made in the field of 1-D nanostructures, including carbon nanotubes and inorganic nanowires, in terms of synthesis, chara...

The electron transport in single-wall carbon nanotubes is one-dimensional and ballistic. Typically carbon nanotubes form tunneling contacts to electrodes and behave as quantum dots at low temperatures. We report on experiments on carbon nanotubes contacted with ferromagnetic metal. In these devices strong hysteretic magnetoresistance is observed at low temperatures. A possible interpretation of...

Chemical vapor deposition was employed to synthesize carbon nanotubes with Ni-loaded MCM-41 and MCM-48 as catalysts and acetylene as precursor at 750°C. Mesoporous Ni MCM-41 and Ni MCM-48 molecular sieves were synthesized by a hydrothermal method and were characterized by XRD and N2 adsorption isotherm. The catalytically synthesized carbon materials were characterized with Raman spectroscopy, N...

We have measured a strictly linear pi plasmon dispersion along the axis of individualized single-wall carbon nanotubes, which is completely different from plasmon dispersions of graphite or bundled single-wall carbon nanotubes. Comparative ab initio studies on graphene-based systems allow us to reproduce the different dispersions. This suggests that individualized nanotubes provide viable exper...