Nanocrystalline Si3N4 with Si-C-N shell structure

Abstract

Nanocrystalline Si3N4 with an amorphous Si-C-N shell structure was synthesized by mechanically activating Si3N4 and graphite powder in argon atmosphere at room temperature. Twenty hours of mechanical activation resulted in occurrence of C-N bond, which can be identified using Fourier transform infrared spectrometry (FT-IR). When the mechanical activation period was extended to 67 h and then to 90 h, the C-N bond was further established. The formation of C-N bond under the mechanical activation for 90 h was further confirmed using X-ray photoelectron spectroscopy (XPS). The thickness of Si-C-N shell is 5-7 nm as observed using high-resolution transmission electron microscope. © 2001 Elsevier Science B.V.