AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Preparation of Novel SiC and Carbon Nanostructures by Induction Heating of Preceramic Silicon-Carbon Nanoparticles
ANNA LÄHDE, Mirella Miettinen, Jouni Hokkinen, Tommi Karhunen, Unto Tapper, Jorma Jokiniemi, University of Eastern Finland
Abstract Number: 290 Working Group: Nanoparticles and Materials Synthesis
Abstract Silicon carbide (SiC) is an important high temperature structural material and high performance semiconductor, which can be operated at high temperatures, high power and high frequencies and in harsh environments. Furthermore, SiC can be used as a precursor material for more advanced structures such as graphene layers. In this study, we report the formation advanced SiC and carbon nanostructures by induction heating. Pre-ceramic Si/C nanoparticles synthesised with the chemical vapour synthesis were annealed in an argon atmosphere at temperatures between 1900 and 2600 oC. The evolution of the particle structure, composition and crystalline phases at different annealing temperatures was studied with SEM/EDS, HR-TEM, XRD and Raman spectroscopy. The annealing caused an increase in the crystallite size from a few nanometers of the untreated precursor to several micrometers in the annealed particles. In addition, the annealing temperature had an effect on the crystalline phase of the formed particles. Below the melting temperature of amorphous silicon carbide (Tm = 2172 ºC), the crystalline phase of SiC-3C was dominant (>96 w-%) while above the decomposition temperature (Tdec = 2577 ºC) a separation of carbon and silicon was observed. Carbon nanoflowers were formed in the sample vessel (T=2600 ºC) while SiC-3C and SiC-6H were formed at lower temperatures near the exit of the sample vessel.