In this paper, we investigate effects of vacancy defects on fracture of carbon nanotubes and carbon nanotube/ aluminum composites. Our studies show that even a one-atom vacancy defect can dramatically reduce the failure stresses and strains of carbon nanotubes. Consequently, nanocomposites, in which vacancy-defected nanotubes are embedded, exhibit different characteristics from those in which p...

Novel carbon nanotubes±metal±ceramic nanocomposite powders and dense materials have been prepared and their microstructure and mechanical properties have been investigated. After a brief review on the structure, synthesis and physical properties of carbon nanotubes, we describe an original catalytic method that produces ceramic±matrix composite powders that contain in situ grown nanotubes. The ...

A carbon nanotube may be viewed as a graphite sheet that is rolled up into a nanometer-scale tubular form (that is, a single-walled carbon nanotube, SWNT) or with additional graphene tubes that form around the core of a SWNT (that is, a multi-walled carbon nanotube, MWNT). Because the graphene sheet can be rolled up with varying degrees of twist along its length, carbon nanotubes can have a var...

The excitement of nano-test-tube chemistry in a single-walled carbon nanotube is exemplified in our study on electron doping in carbon nanotubes. Electron doping through the 1D van Hove singularity of single-walled carbon nanotubes is realized via a chemical reaction of an encapsulated organocerium compound, CeCp3. The decomposition of CeCp3 inside the carbon nanotubes increases the doping leve...

Internal functionalization of single-walled nanotubes is an attractive, yet difficult challenge in nanotube materials chemistry. Here we report single-walled metal oxide nanotubes with covalently bonded primary amine moieties on their inner wall, synthesized through a one-step approach. Conclusive molecular-level structural information on the amine-functionalized nanotubes is obtained through m...

This paper discuss about the critical review on design of carbon nanotube based MEMS piezoresistive pressure sensors, use of different types of carbon nanotubes such as multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWNTs) and vertically aligned carbon nanotubes (VANTs), sensing mechanism, applications, etc. The structural deformation of the piezoresistive nano structur...

Controlled doping of carbon nanotubes is elemental for their electronic applications. Here we report an approach to tune the polarity and degree of doping of single-walled carbon nanotubes via filling with nickelocene followed by encapsulated reactions. Using Raman, photoemission spectroscopy and transmission electron microscopy, we show that nickelocene molecules transform into nickel carbides...

A facile, two-step method for chemically attaching single-stranded DNA to graphitic surfaces, represented here by carbon nanotubes, is reported. In the first step, an azide-containing compound, N-5-azido-nitrobenzoyloxy succinimide (ANB-NOS), is used to form photo-adducts on the graphitic surfaces in a solid-state photochemical reaction, resulting in active ester groups being oriented for the s...

A brief historical review of carbon nanotube research is presented and some basic definitions relevant to the structure and properties of carbon nanotubes are provided. Carbon nanotubes are unique nanostructures that can be considered conceptually as a prototype one-dimensional (1D) quantum wire. The fundamental building block of carbon nanotubes is the very long all-carbon cylindrical Single W...

Low-frequency dielectric responses of carbon nanotubes are important for their manipulation, separation, and electronic applications. Here we report the first experimental measurement of near-dc polarization of individual carbon nanotubes by using modified scanning force microscopy techniques. The transverse polarizability of carbon nanotubes is equivalent to solid cylindrical media with a diel...