High-Pressure Synthesis of sp~2-Bonded Carbon Nitrides

摘要

We have synthesized amorphous sp~2-bonded carbon nitrides at high pressure. A precursor composed of carbon and nitrogen, tetracyanoethylene, was compressed in a diamond anvil cell and laser heated to approximately 2000℃. Transmission electron microscopy, electron diffraction, electron energy loss spectroscopy, and energy-dispersive X-ray analysis have been used to characterize the structure, bonding, and composition of the carbon nitrides. The amount of nitrogen incorporated into the network increases with pressure, ranging from 24% (C_3N) at 18 GPa to 38% at 42 GPa (C_3N_(1.9)), which represents the most nitrogen-rich carbon nitride yet prepared under pressure. A crystalline carbon phase is also found.