"碳点"是永远都是碳点吗? 通过溶液和纯固体中的结构和动态研究证明了它们的超分子性质
Diogo A Sousa1,2, Mário N Berberan-Santos2, José V Prata1,3
1Department of Chemical Engineering Instituto Superior de Engenharia de Lisboa, Instituto Politécnico de Lisboa, 1959-007, Lisbon, Portugal.
Chemistry (Weinheim an der Bergstrasse, Germany)
|November 9, 2023
概括
碳点 (CD) 不是固体纳米粒子,而是动态组装的超分子结构. 这一发现基于结合的固态和溶液分析,重新定义了这些碳材料的形态.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 超分子化学 超分子化学
背景情况:
- 碳点 (CD) 是广泛研究的纳米材料,在传感和生物成像中具有应用.
- 它们的固态形态学和溶液行为一直受到争论,影响了它们的表征和应用.
- 了解CD的精确结构对于优化其性能至关重要.
研究的目的:
- 为碳点 (CD) 在固态和溶液状态的形态提出一个全面的模型.
- 调和应用在固态和溶液分析中的各种分析技术的观察结果.
- 为了阐明CD的光发光特性的结构基础.
主要方法:
- 高分辨率传输电子显微镜 (HRTEM) 和原子力显微镜 (AFM) 用于固态成像.
- 矩阵辅助激光脱/电离 (MALDI) 质谱 (MS) 用于固态分子分析.
- 脉冲场梯度 (PFG) -NMR光谱学,时间解析光异性学 (TRFA) 和光光谱学用于溶液状态的表征.
主要成果:
- 一个连接碳点 (CD) 固态和溶液数据的一致模型.
- 在HRTEM/AFM中观察到的"纳米粒子"是超分子组件,而不是有共价结合的实体.
- 这些组件在溶剂去除后从较小的分子物种动态形成.
- 在溶液中,CD存在于相对较小分子的松散协会中.
结论:
- 碳点 (CD) 是超分子实体,而不是离散的纳米粒子,由非共价相互作用形成.
- 由于动态自组装,CD的形态取决于它们的状态 (固体与溶液).
- 这种超分子模型为碳点结构和特性,特别是光发光,提供了统一的理解.
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