超越性:磁力诱导二元纳米晶超级格子中的准晶体结构的形成
Zhijie Yang1,2, Jingjing Wei1,2, Pierre Bonville3
1†Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, F-75005, Paris, France.
Journal of the American Chemical Society
|March 19, 2015
概括
(Co) 和银 (Ag) 纳米晶体的二元超级晶体表现出基于Co纳米晶体结晶度和温度的不同结构. 磁相互作用和力决定了超级晶格的形成和密度.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 磁力学 磁力学 是一种
背景情况:
- 二元纳米晶体超级网提供可调节的特性.
- 控制超级网格结构对于高级应用至关重要.
- 构成纳米晶体的结晶性和磁性影响自我组装.
研究的目的:
- 为了研究 (Co) 纳米晶体结晶性对二进制Co/Ag超晶格形成的影响.
- 探索温度和Co纳米晶体大小对超级晶格结构的作用.
- 了解控制自组装的潜在驱动力.
主要方法:
- 无形和晶体 (Co) 纳米晶体的合成.
- 使用Co和银 (Ag) 纳米晶体制备二进制超级网格.
- 使用各种技术对超级格子结构的描述.
- 温度和纳米晶体大小的系统变化.
主要成果:
- 无形Co纳米晶在25°C时产生由驱动的NaCl类型的超级晶格.
- 铁磁晶体Co纳米晶体在25°C时形成准晶体和较少包装的相.
- 在65°C时,Co纳米晶体变得超偏磁,导致AuCu3型和AlB2型结构.
- 减少的Co纳米晶体大小 (7nm) 导致稳定的AlB2型超级晶格,独立于Co结晶度.
结论:
- Co-Co磁相互作用和力是Co/Ag超级晶格形成的关键驱动因素.
- Co纳米晶体的结晶性在室温下显著影响由此产生的超级晶格结构.
- 温度诱导的过渡到超偏磁状态和减少的Co纳米晶体大小促进了特定的,稳定的超晶格结构的形成.
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