High-pressure bulk synthesis of crystalline C6N9H3 center dot HCl: A novelC3N4 graphitic derivative

A novel carbon nitride compound, structurally related to the proposed graph itic phase Of C3N4, has been synthesized in a bulk well-crystallized form. The new material. with stoichiometry C6N9H4Cl, was prepared through a solid -state reaction of 2,4,6-triamino-1,3,5-triazine with 2,4,6-trichloro-1,3,5 -triazine at 1.0-1.5 GPa and 500-550 degreesC and also through a self-react ion of 2-amino-4,6-dichloro-1,3,5-triazine at similar conditions. X-ray and electron diffraction measurements on the yellowish compound indicate a hex agonal space group (P6(3)/m) with cell parameters of a = 8.4379(10) Angstro m and c = 6.4296(2) Angstrom. This new compound possesses a two-dimensional C6N9H3, framework that is structurally related to the hypothetical P6m2 gr aphitic phase of C3N4, but with an ordered arrangement Of C3N3 Voids. The l arge voids in the graphene sheets are occupied by chloride ions with an equ ivalent number of nitrogen atoms on the framework protonated for charge bal ance. The composition of the sample was determined by bulk chemical analysi s and confirmed by electron energy loss (EELS) spectroscopy. The chemical a nd structural model is consistent with bulk density measurements and with t he infrared and C-13 NMR spectra. This work represents the first bulk synth esis of a well-characterized and highly crystalline material containing a c ontinuous network of alternating carbon and nitrogen atoms.