Development of Si2N2O, Si3N4 and SiC ceramic materials using rice husk

Abstract The presence of silicon in rice husk has been established by its chemical and thermal degradation. The bonding between Si and C have been studied by IR spectroscopy. The existence of IR peak at 800 cm 1 shows SiC bonding in raw rice husk, which is shifted to 790 cm 1 during coking and pyrolysis. ESCA study of surface showed Si, C, O and F to be present; Si in the form of SiC x and SiO x and C as SiC x and CH x . On sputtering, the SiO x and CH x species decrease with increase of SiC x level. The formation of SiC from coked rice husk and Si 3 N 4 and Si 2 N 2 O from HCl treated rice husk has been observed at 1200–1400 °C under N 2 and NH 3 atmosphere, respectively. The chemical analysis of raw rice husk and products are tabulated. The XRD analyses shows the presence of different phases in the products. A new mechanism for the development of these ceramic materials has been proposed.