The synthesis of a silicon-containing quaternary nitride, CaAlSiN3, in the ammonia system under supercritical conditions was reported. An alloy with the composition of Ca0.992Eu0.008AlSi was made by melting the constituent metals (Ca >99.5%, Eu >99.0%, Al 99.999%, Si 99.999%) followed by subsequent quenching in argon. The sample was loaded in a nickel tube in a high-pressure autoclave and the synthesis was performed in 100 MPa supercritical ammonia. At 400°C, the black alloy powder changed to a white product of ammonometallates. It was extremely sensitive to moisture, releasing ammonia gas and some times sparkling when it was carefully removed from the nickel tube in air. X-ray diffraction (XRD) indicated that the ethanol- washed sample was amorphous. This synthetic route may be able to produce a variety of forms of multinary nitrides from nanostructures to large crystals.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Materials Chemistry