A novel hybrid method combining ASP with PECVD for in-situ low temperature synthesis of vertically aligned carbon nanotube films

Abstract

In this study, an in-situ low temperature method to cost-effectively grow vertically aligned carbon nanotube (VACNT) films has been developed by combining advanced active screen plasma (ASP) technique with plasma enhanced chemical vapour deposition (PECVD). A novel active screen consisting of 316 stainless steel cylinder with double top lids was designed for the in-situ low-cost high-efficient preparation of catalyst films within a PECVD device, and VACNT films were grown from the catalyst films subsequently at low temperatures (≤500°C). The deposited catalyst films and the VACNT films were characterised by SEM, AFM, XRD, Raman and TEM/EDS. The results show that the catalyst films consist of stainless steel nanoparticles with sizes around 50nm. The growth of the CNTs is related to the PECVD temperature and the density of the CNTs is determined by the status of the catalyst films. The CNTs are multiwalled with nanoparticles at their tips. The mechanisms behind the in-situ low temperature synthesis are discussed based on the plasma physics, growth parameters and physical status of the catalyst films.