Synthesis of Carbon Nitride and its incompressibility

2012 Fiscal Year Final Research Report

• Project/Area Number: 24656021
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Applied materials science/Crystal engineering
• Research Institution: Okayama University of Science
• Principal Investigator: TAKARABE Kenichi 岡山理科大学, 理学部, 教授 (50122388)
• Project Period (FY): 2012
• Keywords: 新機能材料 / 窒化炭素

Research Abstract

The purpose of this research program was to synthesis the carbon nitride C3N4 predicted to be harder than diamond within one year. To reach the goal of this research, the research strategy was in the way that 1)the synthesis of H and O free C3N4 nanoparticle, 2) then subjecting that to high-temperature and high-pressure to transform the nanoparticle into the superhard C3N4. The understanding of the crystal structure of non H and O free C3N4HxOy nanoparticle was progressed, which was the starting point of this research program. It is the nano and amorphous particle which consists of an extended layer with a heptazine unit. In C3N4HxOy nanoparticle some nitrogen is terminated by hydrogen, which inhibits to complete the extended layer. The oxygen bonds to the carbon as an epoxy structure or other forms. By subjecting this C3N4HxOy nanoparticle, at the certain high-temperature and high-pressure(for example, about 1700K and 40 GPa) the new carbon-nitride C3N2(CH2) crystal was surely synthesized. The C3N2(CH2) crystal consists of the tetrahedral unit with the C-N single bond and the bridging bond with the terminating hydrogen. The C-N single bond has the compressibility as same as that of diamond revealed by the high-pressure x-ray diffraction study under pressure. This result is important for us that we pursue the superhard material relying on the strength of theC-N single bond. We optimized the synthesis process of carbon nitride nanoparticle and the C3N4Hx nanoparticle with almost O-free is synthesized. But we need some more study to synthesize the C3N4 nanoparticles without H and O.

Research Products

• [Journal Article] Bulk modulus and structural changes of new crabon-nitride-related Material C2N2(CH2) under pressure:the strength of carbon-nitrogen single bond (2013)
  • Author(s): Masaya Sougawa, Kenichi Takarabe, Yoshihisa Mori, Taku Okada, Takehiko Yagi, Hiroaki Kariyazaki, and Koji Sueoka
  • Journal Title: Journal of Applied Physics Volume: 113 Pages: 053510-1-053510-5
  • DOI: DOI:10.1063/1.4789020
  • Peer Reviewed
• [Journal Article] Electronic Structure of C2NX(X=O, NH,CH222):Wide Band Gap Semiconductors (2012)
  • Author(s): Kenichi Takarabe, Masaya Sougawa,Hiroaki Kariyazaki, and Koji Sueok
  • Journal Title: Journal of Applied Physics Volume: 112 Pages: 013537-1-013537-6
  • DOI: DOI:10.1063/1.4731749
  • Peer Reviewed
• [Journal Article] (2012)
  • Author(s): M Sougawa, T Sumiya, K Takarabe, Y Mori, T Okada, H Gotou, T Yagi, D Yamazaki, N Tomioka, T Katsura, H Kariyazaki, K Sueoka and S. Kunitsugu
  • Journal Title: Journal of Physics:Conference Series Volume: 377 Pages: 12028-1-12028-4
  • DOI: DOI:10.1088/1742-6596/377/1/011001
  • Peer Reviewed
• [Presentation] Carbon nitride Diversity (2013)
  • Author(s): K.Takarabe
  • Organizer: Materials at Extreme Conditions
  • Place of Presentation: Celebrity reflection(Florida, USA)
  • Year and Date: 20130300
• [Presentation] Study on C-N-H-O system near the composistion of C3NHxOy andC2N2X(X=O, NH, CH24) under pressure (2012)
  • Author(s): K.Takarabe
  • Organizer: The joint 6th Asian Conference for High Pressure Research and International Forum on High Pressure Sciences
  • Place of Presentation: 中国物理研究院(北京、中国)
  • Year and Date: 20120800