SWCNT-functionalise

Resonance Raman excitation profiles were measured for individually dispersed SWCNT in aqueous solution (excitation 695-985 nm.).218 The IR and Raman spectra of SWCNT functionalised by long-chain hydrophobic groups show that the fundamental structure is unchanged on modification.219 A review has appeared of Raman data for SWCNT and DWCNT, especially the conversion of C60/SWCNT peapods into DWCNT at high temperatures.220... 

Further to this, the increasing activities in the field of biosensors based upon CNT-FETs could strongly benefit from the development of more elaborate (electro-)chemical functionalisation methods, in particular with regard to achieving ultimate selectivity and biocompatibility [74]. Another stimulating impact may be on the elucidation of the exact mechanism by which SWCNT-FETs detect analytes in solution, specifically whether charge transfer or enhanced carrier scattering is the predominant effect of molecule adsorption [39, 75]. 

Coated and functionalised single-walled carbon nanotubes (SWCNTs) as gas sensors... 

Abstract This chapter focuses on the performances of gas sensors based on single-walled carbon nanotubes (SWCNTs).The chapter first reviews chemiresistor and field-effect transistor sensor architectures. Theoretical models based on doping effect and Schottky barrier modulation are correlated to the percolation of metallic carbon nanotubes. The functionalisation strategies of carbon nanotubes, used to acquire a gas selectivity, are discussed and offer promising application for the monitoring of air quality, or military and medical applications. 

Although SWCNTs show attractive features, the development of selective gas sensors based on SWCNTs remains a great challenge. Several methods exposed in Section 10.4 have been explored to overcome this problem. The most mature routes to reach gas selectivity are focused on the chemical covalent or non-covalent functionalisation of SWCNTs, the decoration of SWCNTs with metallic nanoparticles and the diversification of the metallic electrodes. 

As has been pointed out by Cantalini et al. (2003), the cross-sensitivity of SWCNT gas sensors can lead to false alarms in a complex atmosphere. To exploit CNT-based devices, it is crucial to find ways to give them selectivity. To modify the chemical activity of SWCNTs and enhance their sensitivity to a specific gas, the common approach is to functionalise the nanotube side-wall. There are two types of functionalisation depending on the binding of the functional group onto the nanotube sidewall covalent functionafisation and non-covalent functionalisation. Covalent functionalisation of SWCNTs is often obtained from the esterification of carboxylic add groups formed on... 

Gas sensors based on bio-functionalised SWCNTs with DNA strands were explored by the University of Pennsylvania group (Staii et al, 2005). DNA preferentially wraps around SWCNTs via Ti-stacking interaction. Compared with CNTFET based on pristine SWCNTs, DNA functionahsed CNTFETs... 

SWCNT-(ODA) SWCNT-[CONHCH2(CH2)i6CH3)[ , octadecylamide functionalised, 89-90 /o SWCNT (carbonaceous purity), bundle dimension diam 2-lOnm x length 0.5-2.0pm, average diameter of individual SWCNT being 1.4nm 0.1nm. It is prepared from the above SWCNT-(COCl) (obtained from... 

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