Polycarbosilane facilitated growth of SiC nanowires from biowaste coconut shell

Abstract

The SiC nanowires were synthesised by the pyrolysis of a mixture of agricultural waste coconut shell (CS) and polycarbosilane (PCS) precursor at 1400°C. The characterisation of synthesised nanowires was carried out by X-ray diffraction, transmission electron microscopy, and Raman spectroscopy. The single crystalline cubic β-SiC nanowires were found to be grown on <111> directions along (111) planes. The SiC nanowires had striped morphology containing stacking faults and twins as a planar defect. The extensive growth of SiC nanowires was owing to the continuous deposition of SiO and CO gaseous over the tiny SiC nuclei from the amorphous SiOC matrix. The vapour–solid (VS) and vapour–phase (VP) mechanisms have played the dominant role in nanowire formation. The 3C-SiC nanowires had striped morphology containing hexagonal 4H-SiC and 6H-SiC stacking faults.