Carbon nanotubes chemical changes

Under ambient conditions, SWNTs are p-type semiconductors. This means that the charge carriers are holes, or the absence of electrons. This class of semiconductors shows an increase in conductivity when electron density is withdrawn and a decrease in conductivity when electron density is donated. This behavior has been observed experimentally for individual SWNTs connected to a set of electrodes. This allows for chemical detection with a simple chemiresistor. This is a device composed of two electrodes which are connected by some material, in this case a single-walled carbon nanotube, which changes resistance upon exposure to a particular analyte. 

Tang, Q. Wang, Y.-L. Chang, and H. J. Dai, An investigation of the mechanisms of electronic sensing of protein adsorption on carbon nanotube devices , Journal of The American Chemical Society 126, 1563 (2004). 

The structure and properties of C2o (8,8) CNT system are explored by quantum chemical and molecular mechanic calculations. The change of the barrier for relative motion of fullerene along the carbon nanotube axis at the Peierls transition is found. The changes of dynamical behavior of the system C2o (8,8) CNT at the transition are discussed. 

Pan ZW, Xie SS, Chang BH et al. (1999) Direct growth of aligned open carbon nanotubes by chemical vapour deposition. Chem Phys Lett 299 97-102... 

Carbon nanotubes since its discovery in 1991 have attracted much attention of researchers due to its unique properties, like high current density, chemical inertness, high mechanical strength, etc. Kaiser et al. [1] pointed out similarity between the resistivity temperature behavior p(T) observed in SWCNTs and that of highly conducting polymers, in particular the change in sign of the p(T) dependence from metallic to non-metallic as T was decreased. 

We learn how the physical and chemical properties of materials change when their crystals become very small. These effects begin to occur when materials have sizes on the order of 1-100 nm. We explore lower-dimensional forms of carbon— fullerenes, carbon nanotubes, and graphene. 

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