纳米粒子超网中的多态性:半导体金属元材料的一个例子
Elena V Shevchenko1, Dmitri V Talapin, Stephen O'brien
1IBM T.J. Watson Research Center, Nanoscale Materials and Devices Group, 1101 Kitchawan Road, Yorktown Heights, New York 10598, USA. eshevche@us.ibm.com
Journal of the American Chemical Society
|June 16, 2005
概括
研究人员发现了结晶纳米粒子的新方法,创造了具有可调节性质的新材料. 这项工作挑战了现有的理论,并为先进的纳米复合材料开发打开了大门.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 晶体学 晶体学是指结晶学.
背景情况:
- 纳米颗粒的合结晶使得能够创建有序的纳米复合材料,具有可调节的特性.
- 硬球近似理论预测纳米粒子结晶的有限稳定的二进制相.
研究的目的:
- 探索超越理论预测形成新的纳米粒子组件的可能性.
- 为了研究化 (PbSe) 和 (Pd) 纳米粒子的结晶行为.
主要方法:
- 使用环状结晶技术组装PbSe和Pd纳米粒子.
- 分析结果的结构,以测量体积和包装密度.
主要成果:
- 成功地将PbSe和Pd纳米粒子结晶成两种不同的多态体,使用AB(13) 立体几何学.
- 确定了一种与硬球包装 (NaZn(13) 类型) 相一致的多态.
- 发现了第二个,意想不到的多态体,其包装密度较低.
结论:
- 基于硬球近似的现有理论不足以预测所有可能的纳米粒子结晶结果.
- 有机被动化纳米晶体结晶需要采用超出简单填充空间原理的各种力量的模型.
- 实现了具有较低包装密度的有序周期结构,展示了纳米复合材料设计的新可能性.
- 介绍了第一个使用PbSe-Pd纳米晶体的二元半导体金属超级网格.
相关概念视频
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