在o-doped化纳米管中的辐射过渡的性质
Gaoyang Gou1, Bicai Pan, Lei Shi
1Hefei National Laboratory for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, PR China.
Journal of the American Chemical Society
|March 13, 2009
概括
化纳米管 (BNNTs) 中的氧杂质产生了新的结构,解释了观察到的辐射过渡. 第一原理计算揭示了这些O-doped BNNTs如何改变电子和光学特性,证实了实验发现.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术 纳米技术
背景情况:
- 化纳米管 (BNNT) 的实验性阴极发光光谱表明氧杂质诱导辐射过渡.
- 在BNNT中氧气影响的精确结构配置和机制尚不清楚.
研究的目的:
- 为了阐明氧化的BNNTs的结构模式.
- 研究氧气替代杂质对BNNTs电子和光学性能的影响.
- 在BNNTs中提供氧气诱导的辐射过渡的理论证据.
主要方法:
- 使用第一原则计算来预测O-doped BNNTs的稳定配置.
- 电子结构,光学属性和振动属性被计算研究.
- 与氧化结构单元进行了比较.
主要成果:
- 预测了O-dopedBNNTs的新型,稳定的B(3) O(6) 组配置,类似于氧化.
- 计算表明,氧气替代杂质引入了类似捐赠体的隙状态.
- 由于氧气兴奋剂,观察到BNNT的光学特性发生显著的变化.
结论:
- 该研究阐明了关于BNNTs辐射过渡的实验发现的起源.
- 理论证据支持在BNNT中存在氧替代杂质诱导的辐射转换.
- 预测的B(3) O(6) 结构为氧气在BNNT特性中的作用提供了洞察力.
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