使用液体细胞传输电子显微镜的单个状纳米粒子的生长动力学
Wan-Gil Jung1, Jeung Hun Park2,3, Yong-Ryun Jo1
1School of Materials Science and Engineering , Gwangju Institute of Science and Technology (GIST) , 123 Cheomdangwagi-ro, Buk-gu , Gwangju , Korea.
Journal of the American Chemical Society
|July 11, 2019
概括
研究人员使用现场液体细胞传递电子显微镜观察黄金尖纳米粒子 (SNP) 的生长. 这项研究揭示了一种新的方法来控制黄金SNP大小,形态和表面等离子体共振 (SPR),而无需添加剂.
科学领域:
- 纳米技术
- 材料科学
- 物理化学
背景情况:
- 对金尖纳米粒子 (Au SNP) 尺寸和形态的精确控制对于可调的表面等离子体共振 (SPR) 是至关重要的.
- 了解Au SNP的生长机制和形态转变需要实时的纳米分辨率观察.
- 目前的合成方法通常依赖于减少或限制剂,限制精确的控制.
研究的目的:
- 通过液体细胞传导电子显微镜 (LCTEM) 调查Au SNPs的现场生长机制和形态转变.
- 建立一种方法来操纵Au SNP特征,包括尺寸,形态,SPR和密度,没有化学添加剂.
- 将生长参数与粒子进化和表面等离子体共振特性相关联.
主要方法:
- 使用现场液体细胞传导电子显微镜 (LCTEM) 来观察单个和多个Au SNP的生长.
- 在观察过程中变化的电子束参数 (大小,剂量率) 和HAuCl4溶液度.
- 进行量化分析与理论模型相结合,以确定生长模式和过渡时间.
主要成果:
- 通过不同的增长阶段观察到Au SNP的演变:反应限制,然后是黄金形成限制的增长.
- 确定了从面状表面到粗表面的转变, 与紫外线光谱的等离子波段的变化相关.
- 证明过渡时间 (tc) 可以通过粒子密度调整,该密度由基于DLVO理论的实验参数调整.
结论:
- 开发了一种用于合成Au SNP的新方法,可控制大小,形态,SPR和密度.
- 通过调整电子束和前体度来操纵Au SNP特征的能力,绕过了减少或限制剂的需要.
- 通过实时现场LCTEM观测,提供了对Au SNP生长动态和形态演变的基本见解.
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