AN ATTEMPT TO PREPARE CARBON NITRIDE BY THERMAL PLASMA CHEMICAL-VAPOR-DEPOSITION FROM GRAPHITE AND NITROGEN

RF induction thermal plasma was applied to the chemical vapor depositi on of carbon nitride from graphite powders and Ar-N-2 gas at about 1 a tm. Low-density and fragile amorphous powder-like bulk deposits whose color is light yellow were obtained. Elementary analysis by a combusti on method and x-ray photoelectron spectroscopy showed that the N/C rat io is higher than that of stoichiometric C3N4. Also, a large amount of hydrogen and oxygen are included, which seems to be due to the absorp tion of moisture and oxygen after exposure to air. Infrared absorption spectra suggest the presence of sp CN and sp(2) CN bonds, and nitroge n-containing polycondensed ring structures. Thermogravimetric analysis with mass spectroscopy shows that the deposits decompose almost compl etely at 800 degrees C, suggesting that the polycondensed rings are no t large and not well cross-linked.