碳化氮 硼化氮 硬度哪个大

碳化氮 硼化氮 硬度哪个大
碳化氮 硼化氮 硬度哪个大

碳化氮 硼化氮 硬度哪个大
应该是氮化碳C3N4和氮化硼BN
氮化硼是一种很特殊的原子晶体
- -我记得它在一定条件下可以像金刚石一样硬 在一定条件下又可以像石墨一样软
如果按照共价键理论来分析的话,C原子半径比B原子小,C-N键键长比B-N键短,因此C-N键键能大 硬度理论上来说也比较大
所以
理论上
C3N4比较硬
只是理论上.

应该是碳化氮吧，因为碳原子的原子直径比硼原子小，所以形成的键短，键能大，硬度大。

根据预测β-氮化硼比金刚石还硬（见英文）。氮化硼的硬度相对于金刚石：
金刚石的Vickers hardness (GPa) 115 而氮化硼 62。
最硬的材料是Aggregated diamond nanorods，ADNRs 集结金刚石纳米棒。aggregated diamond nanorods have a modulus of 491 gigapascals (GPa),...

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根据预测β-氮化硼比金刚石还硬（见英文）。氮化硼的硬度相对于金刚石：
金刚石的Vickers hardness (GPa) 115 而氮化硼 62。
最硬的材料是Aggregated diamond nanorods，ADNRs 集结金刚石纳米棒。aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), while a conventional diamond has a modulus of 442 GPa. ADNRs are also 0.3% denser than regular diamond. The ADNR material is also harder than type IIa diamond and ultrahard fullerite.
“Beta carbon nitride (β-C3N4) is a material predicted to be harder than diamond.[1]”
[1] http://www.nature.com/news/2000/000511/full/news000511-1.html
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].
[2]^ A. Liu and M. Cohen, "Prediction of New Low Compressibility Solids" Science 245, pp. 841-842 (1989)
[3]^ C. Niu, Y.Z. Lu and C.M. Lieber, "Experimental Realization of the Covalent Solid Carbon Nitride" Science 261, 334 (1993)
[4]^ J. Martín-Gil, F.J. Martín-Gil, M. Sarikaya, M. Qian, M. José-Yacamán, A. Rubio, "Evidence of a low-compressibility carbon nitride with defect-zincblende structure" J. Appl. Phys 81, pp. 2555-2559 (1997)
[5]^ L.W. Yin, M.S. Li, Y.X. Liu, J.L. Sui, J.M. Wang, "Synthesis of beta carbon nitride nanosized crystal through mechanochemical reaction" J.Phys.: Condens. Matter 15, pp. 309-314 (2003)
[6]^ L.W. Yin, Y. Bando, M.S. Li, Y.X. Liu, Y.X. Qi, "Unique Single-Crystalline Beta Carbon Nitride Nanorods" Advanced Materials 15, pp. 1840-1844 (2003)

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理论上是碳化氮(C3N4）更硬，但目前其合成方法尚未完全解决，实际应用较少。现对而言立方氮化硼CBN的先关技术更为成熟。