n-diamond from catalysed carbon nanotubes: synthesis and crystal structure

The phase composition and morphology of black powder samples synthesized by pyrogenation of carbon nanotubes and colloidal Fe(OH)3 were investigated using x-ray diffraction (XRD) and transmission electron microscopy. A new kind allotrope of carbon, 'new diamond' (n-diamond), was obtained in the final black powder when the treatment temperature was higher than 1000 °C. As the treatment temperature reached 1400 °C, the peak intensity of the n-diamond achieved its maximal value and the estimated yield rate was about 20%. The average size of the n-diamond nanometric particles was around 20 nm. Using the least squares refinement method and XRD pattern simulation technology, the crystal structure of n-diamond was studied.