在单晶金属有机框架颗粒中通过氧化链接裂变进行定向雕刻
Lianshun Luo1, Wei-Shang Lo2, Xiaomeng Si1
1School of Physical Science and Technology , ShanghaiTech University , Shanghai 201210 , China.
Journal of the American Chemical Society
|November 30, 2019
概括
一种新的氧化链裂 (OLC) 工艺精确地设计单晶金属有机框架 (MOF). 这种方法可以创建空洞和黄的MOF结构,从而实现尺寸选择性催化并防止纳米粒子聚合.
科学领域:
- 材料科学
- 纳米技术
- 化学工程
背景情况:
- 金属有机框架 (MOF) 为各种应用提供可调节的孔隙性和高表面积.
- 对MOF形态和内部结构的精确控制对于高级功能至关重要.
- 现有的MOF修改方法往往缺乏空间控制和可扩展性.
研究的目的:
- 开发一种用于控制单晶MOF结构的新方法.
- 创建独特的MOF架构,
- 展示该方法用于封装纳米粒子并实现尺寸选择性催化.
主要方法:
- 开发了一种氧化链体裂变 (OLC) 工艺,利用选择性降解2,5-二基甲酸链体.
- 控制氧化物种的产生和扩散到直接框架蚀刻.
- 在预嵌入的Palladium纳米粒子 (Pd NPs) 周围启动OLC以进行局部修改.
主要成果:
- 实现了对MOF框架的可控剪切,产生各种单晶空洞和黄结构.
- 在单个MOF颗粒中成功地限制了多个PdNP,形成了多黄架构.
- 已证明能有效地保护NP免受聚合,并实现了尺寸选择性催化.
结论:
- OLC过程为MOF纳米结构的工程提供了通用和精确的工具.
- 开发的多黄MOF架构对于稳定纳米粒子和实现先进的催化应用非常有效.
- 这一战略为设计具有定制性质的功能纳米材料开辟了新的途径.
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