根据热力学模型定制Cu-Ag纳米和核心纳米晶体的形态
Wojciech T Osowiecki1,2, Xingchen Ye2, Pratima Satish2
1Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States.
Journal of the American Chemical Society
|June 19, 2018
概括
研究人员合成了独特的铜银 (Cu-Ag) 双金属纳米新月,通过热力学模型控制它们的形状. 这些纳米粒子具有可调节的等离子体特性和催化潜力.
科学领域:
- 材料科学
- 纳米技术
- 物理化学
背景情况:
- 控制双金属异质纳米晶体的形成对等离子体和催化非常重要.
- 预测和操纵纳米粒子形态可以提高它们的功能性质.
研究的目的:
- 合成和特征稳定,单分散的Cu-Ag双金属纳米粒子与不寻常的元素安排.
- 研究控制纳米粒子形态的热力学原理,特别是纳米半月形状的形成.
- 探索合成的Cu-Ag纳米粒子的氧化稳定性和光学特性.
主要方法:
- 通过溶液处理合成Cu-Ag双金属纳米粒子.
- 使用无空气扫描传输电子显微镜 (STEM) 和能量分散式X射线光谱 (EDS) 进行表征.
- 用热力学模型将表面/接口能量与纳米粒子形态相关联.
主要成果:
- 一个稳定的,单分散的Cu-Ag纳米半月形状的发现.
- 在单个纳米晶体内识别特定的元素安排.
- 证明纳米粒子形态由热力学控制,并可根据Ag含量调节.
- 观察 Cu-Ag 纳米成 Ag@Cu2O 的选择性氧化,而核心 Cu@Ag 纳米颗粒保持稳定.
结论:
- 一个热力学模型成功地预测并解释了Cu-Ag纳米新月形态的形成.
- 可调节的Cu-Ag纳米颗粒的等离子体和带间吸收,受组成和氧化状态的影响,为光驱动催化提供了潜力.
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