24小时热门版块排行榜

返回列表

【奖励】本帖被评价205次，作者xiejf增加金币 161.6 个

当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖

xiejf

专家顾问 (文学泰斗)

[资源] Science最新研究进展：原位观测Oriented Attachment生长机理

Oriented Attachment是纳米材料的一种重要生长机理，而直接原位的观测这种机理因高分辨电镜的特殊条件要求一直是一个难题。美国科学家通过特殊手段原位观测了这一机理的发生，发现小颗粒会持续的旋转并发生相互作用，形成很好的晶格匹配，进而形成大晶粒。

摘要：
The oriented attachment of molecular clusters and nanoparticles in solution is now recognized as an important mechanism of crystal growth in many materials, yet the alignment process and attachment mechanism have not been established. We performed high-resolution transmission electron microscopy using a fluid cell to directly observe oriented attachment of iron oxyhydroxide nanoparticles. The particles undergo continuous rotation and interaction until they find a perfect lattice match. A sudden jump to contact then occurs over less than 1 nanometer, followed by lateral atom-by-atom addition initiated at the contact point. Interface elimination proceeds at a rate consistent with the curvature dependence of the Gibbs free energy. Measured translational and rotational accelerations show that strong, highly direction-specific interactions drive crystal growth via oriented attachment.

.

[ 来自科研家族材料家族 ]

回复此楼

» 本帖附件资源列表

欢迎监督和反馈：小木虫仅提供交流平台，不对该内容负责。
本内容由用户自主发布，如果其内容涉及到知识产权问题，其责任在于用户本人，如对版权有异议，请联系邮箱：xiaomuchong@tal.com
附件 1 : Direction-SpecificInteractionsControlCrystalGrowthbyOrientedAttachment.pdf

2012-05-25 10:00:43, 9.73 M