High-temperature high-pressure synchrotron X-ray diffraction study of C3N4

Pure beta-C3N4 with symmetry group P63/M (176) and cubic C3N4 were synthesized in laser heated diamond anvil cell under high pressure and high temperature conditions. The precise XRD analysis (R-wp = 2.8) was successfully performed to refine the structures of graphite C3N4 and beta-C3N4. Moreover, the structural transition from beta-C3N4 to cubic C3N4 was monitored by In-situ high pressure synchrotron X-ray diffraction analysis.