Synthesis of highly oriented carbon nanotube thin films by nickel functionalisation

A novel method for fabricating thin films of oriented and densely packed metal functionalised carbon nanotubes (m-CNT) on silicon substrates is described. Positively charged metal ion from their salt solution was adsorbed on carboxylic acid funtionalised (f) CNT by electrostatic interaction. Subsequently, the aqueous dispersion of m-CNT was cast on silicon substrate forming m-CNT thin films after evaporation. Thin films of f-CNT and m-CNT were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) and Raman spectroscopy analysis. The mechanism of functionalisation and orientation of CNTs is discussed briefly. (c) 2006 Published by Elsevier B.V

Nitrogen and hydrogen related infrared absorption in CVD diamond films

In this paper, we investigate on the presence of hydrogen and nitrogen related infrared absorptions in chemical vapour deposited (CVD) diamond films. Investigations were carried out in cross sections of diamond windows, deposited using hot filament CVD (HFCVD). The results of Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) and Raman spectroscopy carried out in a cross section of self-standing diamond sheets are presented. The FTIR spectra showed several features that have not been reported before. In order to confirm the frequency of nitrogen related vibrations, ab-initio calculations were carried out using GAMESS program. The investigations showed the presence of several C-N related peaks in one-phonon (1000-1333 cm(-1)). The deconvolution of the spectra in the three-phonon region (2700-3150 cm-1) also showed a number of vibration modes corresponding to sp(m)CH(n) phase of carbon. Elastic recoil detection analysis (ERDA) was employed to compare the H content measured using FTIR technique. Using these measurements we point out that the oscillator strength of the different IR modes varies depending upon the structure and H content of CVD diamond sheets. (c) 2005 Elsevier B.V. All rights reserved