在表面上重复Alkoxysilane组装:移植与溶液中的同型凝结
Yannick Millot1, Antoine Hervier1, Jihed Ayari1
1Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS), 4 place Jussieu, F-75005 Paris, France.
Journal of the American Chemical Society
|March 17, 2023
概括
氨基三西兰 (APTES) 主要通过同位凝结而不是移植在上形成物理吸附网络. 这挑战了APTES表面组装在二氧化和酸盐上的常见理解.
科学领域:
- 材料科学
- 表面化学
- 纳米技术
背景情况:
- 表面功能化通常使用表面醇的凝.
- 人们普遍认为,阿米诺三西兰 (APTES) 通过异构凝结,由其氨基组催化,很容易移植到表面.
研究的目的:
- 量化研究APTES在酸盐和酸盐表面上的组装机制.
- 区分APTES接种 (异质凝结) 和导致物理吸收的多重凝结.
- 将APTES组件与烯三基 (CPTCS) 进行比较.
主要方法:
- 使用固态29SiNMR光谱进行定量分析.
- 分析的重点是来自西兰 (T物种) 和 (Q物种) 的信号的比例.
- 使用T-O-T/Q-O-T桥梁的比率来估计移植与同质凝结.
主要成果:
- 中三西兰 (CPTCS) 显示出明显的接到表面的证据.
- 氨基三西兰 (APTES) 显示了最小的西兰醇组消耗,表明移植有限.
- 大多数酸盐和酸盐表面的APTES存在于同型凝结网络中,主要是物理吸附,直接固酸盐不到6%.
结论:
- 在酸盐和酸盐上APTES组装的普遍机制是同体凝结,形成物理吸附网络,而不是直接接种.
- 关于APTES通过异构凝结接种的既定观点需要修订.
- 使用APTES的表面功能化主要涉及西兰的自我凝结,与表面西兰醇的直接相互作用有限.
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