Powder synthesis and characterization of amorphous carbon nitride

Carbon nitride powder has been prepared by solid-state reaction between cya nuric chloride or its fluoro analogue and lithium nitride. The determined, by elemental analysis, atomic N/C ratio (1.33) in the synthesized material is entirely consistent with the C3N4 stoichiometry. Combined material chara cterization data, obtained by Fourier transform infrared, Raman, UV-visible , (C-13) magic-angle spinning NMR, X-ray photoelectron spectroscopy, therma l gravimetric analysis/differential thermal analysis, and pyrolysis-electro n ionization mass spectrometry methods, provide substantial evidence for gr aphite-like sp(2)-bonded structure composed of building blocks of s-triazin e rings bridged by the 3-fold coordinated nitrogen atoms in the bulk carbon nitride. As indicated by X-ray and scanning electron microscopy analytical data, the material is amorphous and changes from turbostratic to more orde red layered graphitic morphology under high pressures. The availability of stoichiometric carbon nitride a-C3N4 in gram quantities, made possible by a developed low-cost synthetic method, facilitates the extensive studies of bulk processing and electromechanical properties, and high-pressure/high-te mperature transformations of this material into superhard crystalline polym orphic phases.