Formation of crystalline carbon nitride powder by a mild solvothermal method

Crystalline carbon nitride powder has been successfully prepared via the liquid-solid reaction between anhydrous C3N3Cl3 and Li3N in benzene at 355degreesC and 5-6 MPa for 12 h. X-Ray diffraction (XRD) indicated that the major part of our brown sample was composed mainly of alpha-C3N4 and beta-C3N4 with lattice parameters of alpha=6.49 Angstrom, c=4.70 Angstrom for alpha-C3N4 and a=6.43 Angstrom, c=2.43 Angstrom for beta-C3N4. X-Ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FTIR), electron energy-loss spectroscopy (EELS) and energy loss near edge structure (ELNES) strongly supported the existence of C-N covalent bonds. The relative N/C ratio is about 0.66. The temperature had an effect on the crystallization of carbon nitride powder. We have shown that the solvothermal technique might hold some promise for synthesizing pure crystalline alpha-C3N4 and beta-C3N4.