Formation of sp3-bonded carbon upon hydrothermal treatment of SiC

Abstract

The composition and structure of carbon produced by selective leaching of silicon carbide under hydrothermal conditions in the temperature range 300-800°C and at pressures <500 MPa were examined by Raman and IR spectroscopy, XRD, SEM, TEM and EDS. The results of this study have demonstrated that various carbon allotropes, including diamond, are formed during hydrothermal treatment of SiC. Their structure varies depending on the experimental conditions and SiC precursor. The formation of sp2 vs. sp3 carbon is discussed.