CVD synthesis of carbon nanofibres with washable support catalyst of potassium fluoride

Abstract

In this paper, the results of the experiments conducted to study the role of the mixtures of NH4OH/KOH or KF as supports for cobalt catalyst, in the production of carbon nanofibres by catalytic chemical vapour deposition method are reported. Also, citric acid was used with the role of foaming agent. Acetylene (C2H2) was used as the source of carbon and mixture of N2 and H2 as the carrier gases. The synthesis reactions were conduced at 700°C under ambient pressure in a horizontal tubular furnace. Characterisation of the carbon nanotubes was carried out using scanning electron microscopy, high transmission electron microscopy, thermogravimetric and Raman spectroscopy. In further investigation, rod-like shaped carbon nanofibres have been discovered under high resolution transmission electron microscopy. The diameter of determined carbon nanofibres by transmission electron microscopy were between 50 and 150 nm. A simple method of purification of crude carbon deposit is also described.