Beta carbon nitride

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A diagram of (β-C3N4). This drawing represents one layer in a 3-dimensional molecule. Each carbon atom has four separate bonds and each nitrogen atom three; bonds not depicted in this diagram are to atoms in the layer above or below this one.

Beta carbon nitride (β-C3N4) is a superhard material predicted to be harder than diamond.[1]

The material was first proposed in 1985 by Marvin Cohen and Amy Liu. Examining the nature of crystalline bonds they theorised that carbon and nitrogen atoms could form a particularly short and strong bond in a stable crystal lattice in a ratio of 1:1.3. That this material would be harder than diamond on the Mohs scale was first proposed in 1989.[2]

The material has been considered difficult to produce and could not be synthesized for many years. Recently, the production of beta carbon nitride was achieved. For example, nanosized beta carbon nitride crystals and nanorods of this material were prepared by means of an approach involving mechanochemical processing.[3][4][5][6]

See also[edit]

References[edit]

  1. ^ Ball, P. (5 Jun 2000). "News: Crunchy filling". Nature. doi:10.1038/news000511-1. 
  2. ^ Liu, A. Y.; Cohen, M. L. (1989). "Prediction of New Low Compressibility Solids". Science 245 (4920): 841–842. doi:10.1126/science.245.4920.841. PMID 17773359. 
  3. ^ Niu, C.; Lu, Y. Z.; Lieber, C. M. (1993). "Experimental Realization of the Covalent Solid Carbon Nitride". Science 261 (5119): 334–337. doi:10.1126/science.261.5119.334. 
  4. ^ Martín-Gil, J.; Martín-Gil, F. J.; Sarikaya, M.; Qian, M.; José-Yacamán, M.; Rubio, A. (1997). "Evidence of a Low-Compressibility Carbon Nitride with Defect-Zincblende Structure". Journal of Applied Physics 81 (6): 2555–2559. doi:10.1063/1.364301. 
  5. ^ Yin, L. W.; Li, M. S.; Liu, Y. X.; Sui, J. L.; Wang, J. M. (2003). "Synthesis of Beta Carbon Nitride Nanosized Crystal through Mechanochemical Reaction". Journal of Physics: Condensed Matter 15 (2): 309–314. doi:10.1088/0953-8984/15/2/330. 
  6. ^ Yin, L. W.; Bando, Y.; Li, M. S.; Liu, Y. X.; Qi, Y. X. (2003). "Unique Single-Crystalline Beta Carbon Nitride Nanorods". Advanced Materials 15 (21): 1840–1844. doi:10.1002/adma.200305307.