在环境压力下将碳化转化为晶体钻石结构的碳
1Drexel University, Department of Materials Engineering, Philadelphia, Pennsylvania 19104, USA. gogotsi@drexel.edu
Nature
|May 18, 2001
概括
研究人员开发了一种新的,具有成本效益的方法,从碳化中合成具有钻石结构的碳. 这种环境压力过程产生了高质量的纳米晶体钻石,具有大规模生产的有前途的机械性能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学工程是化学工程的重要组成部分.
背景情况:
- 目前的合成钻石生产方法 (高压,化学蒸汽沉积,冲击波) 在体积和成本方面面临限制.
- 替代性钻石生长技术往往会产生非常低的产量,并且仅限于小体积或薄膜.
研究的目的:
- 开发一种新,可扩展和具有成本效益的合成钻石结构碳的方法.
- 在环境条件下探索碳化转化为钻石结构碳的过程.
主要方法:
- 碳化在温度低于1000°C和环境压力下使用含气体进行处理.
- 气被引入气体混合物中,以稳定钻石结构的碳形成.
- 由此产生的纳米和微晶碳结构的特征,包括它们的机械性能.
主要成果:
- 通过从碳化中提取来成功合成纳米和微晶体钻石结构碳 (立方和六角形).
- 实现了稳定的转换,平均晶体质大小为5-10纳米.
- 生产的纳米晶体涂层的硬度>50 GPa,Young的模量高达800 GPa.
结论:
- 开发的方法为大规模生产晶体钻石结构碳提供了可行的途径.
- 该过程是高效的,允许由于线性反应动力学的完整样本转换.
- 合成的钻石结构碳具有出色的机械性能,适合各种应用.
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