Abstract: A new technique was developed to synthesize the superhard material C₃N₄ in which high pressure and temperature needed in the reaction were supplied by RDX explosive charge and dicyandiamide (C₂H₄N₄) was used as the primary precursor. The structure, valencebond character and elemental composition of the sample prepared under 16GPa pressure were characterized by the scanning electron microscope (SEM), X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy analysis (EDS) and infrared spectrometer (FTIR) respectively. The results show that the XRD pattern is in accordance with the theoretical value, i.e., α-C₃N₄, β-C₃N₄, graphite-C₃N₄ and intercrystal-C₃N4 are recognised in the products. The mass ratio of carbon to nitrogen is about 1.00∶2.98 and nitrogen is mostly bonded with carbon by CN. Some hexagonal β-C₃N₄ particles with size of 2μm are observed through SEM. Powder of polycrystalline C₃N₄ is synthesized successfully and its formation mechanism is discussed.

Key words: shock, synthesis, polycrystalline, C₃N₄