Rh@Au核心外纳米晶体,核心在拉力应变中,外在压力应变中
Veronica D Pawlik1, Annemieke Janssen1, Yong Ding2
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
The journal of physical chemistry. C, Nanomaterials and interfaces
|January 31, 2024
概括
研究人员在纳米晶体上实现了黄金的表轴生长,创造了高度紧张的核心外结构. 这种受控合成克服了对先进的催化应用的格子不匹配的挑战.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 催化剂是一种催化剂.
背景情况:
- 双金属纳米晶体通过结合两个元素提供可调节的特性.
- 核心外结构在催化过程中很有价值,利用网格应变.
- 较大的格子不匹配 (>5%) 通常会导致缺陷和非上轴生长.
研究的目的:
- 在 (Rh) 纳米立方体上实现黄金 (Au) 的表轴生长.
- 为了创建具有显著格子不匹配 (7.2%) 的Rh@Au核心外纳米晶体.
- 研究用于控制双金属纳米晶体中菌株和形态的方法.
主要方法:
- 合成小 (4.5 nm) 的Rh立方种子.
- 在温和的条件下,Au外的长轴沉积.
- 使用NaOH和KBr调运动参数.
主要成果:
- 成功形成Rh@Au截断的八面体,并具有表轴生长.
- 拉伸性菌株在小Rh种子中的均分布.
- 控制的核化导致中心位置的核和狭窄的尺寸分布.
结论:
- 尽管有很大的格子不匹配,但可以实现Au on Rh的表轴生长.
- 小种子大小和受控的合成参数对于管理菌株至关重要.
- 这种方法可以为潜在的催化应用创造高应变的双金属纳米晶体.
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