Dye stabilised nanoemulsions as powerful platform for the synthesis of nanoparticles

染料稳定的纳米乳液作为合成纳米颗粒的强大平台

• 批准号: 431859640
• 负责人: Professor Dr. Ulrich Ziener
• 金额: --
• 依托单位: Institut für Theoretische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/431859640?language=en
• 关键词: Dye; stabilised; nanoemulsions; powerful; platform

Small, narrowly distributed silica nanoparticles (ca. 6–30 nm diameter) can be prepared with high precision in dye stabilized nanoemulsions via a sol-gel process. Alternatively, very homogeneous capsules can be generated in the nanoemulsions depending on the dyes. There are assumptions on the mechanism of the process but detailed data on a molecular level is missing. In the beginning of the project investigations on the mechanism of formation of the silica particles and capsules shall be performed with the help of various characterization methods (1H-, 13C-, 29Si-NMR-, Raman-, IR-spectroscopy, SAXS/WAXS, TEM, SEM) and modelling with molecular dynamics. SAXS/WAXS will play a pivotal role because in preliminary work structural information on the arrangement of the dye molecules as well as on the inorganic particles at the interface could be obtained. Those shall be refined and combined with time dependent measurements at the synchrotron to gather important data on the kinetics of the sol-gel process. Through the gained information, the concept shall be extended in terms of a universal platform. Copolymerizations and postfunctionalizations of the particles’ surface will be carried out. The mild reaction conditions (pH ca. 7, no further additives) shall also allow to employ sensitivesurface modificators like peptides or proteins. Because of the reaction at the interface particles with Janus morphology are expected. Furthermore, core-shell morphologies and colloidosomes should be accessible by this process. In addition, it is planned to substitute the silica precursors by titanium containing monomers to obtain small and uniform TiO2 nanoparticles. Caused by the precuorsors' hydrolytic lability there might be the necessity to fall back on non-aqueoussystems. A striking advantage of the dyes over classical surfactants is that the former can be easily removed by washing which is followed without problems visually or spectroscopically. From the methodical viewpoint, there will be a strong focus of the project on static lightscattering experiments. They shall help to elucidate the mechanism of formation of the nanoparticles and –capsules without laborious sample preparation and to control (online) the process of their formation. The project focuses on the synthesis of new materials with strong methodical support in order to better understand and control the synthesis. The selection of the materials is made by application aspects but the direct realization of applications would gobeyond the scope of the project.The project focusses on three key issues: 1) mechanism of stabilization by the dyes, 2) role of the dyes in the sol-gel process and 3) extension of the concept to further morphologies and materials.Summarizing, the project’s versatility, flexibility and high potential of dye stabilized nanoemulsions as interfacial reactors for sol-gel processes shall be demonstrated.

在染料稳定的纳米乳液中，通过溶胶-凝胶法可以高精度地制备细小、分布窄的二氧化硅纳米颗粒(直径约6-30 nm)。或者，根据染料的不同，可以在纳米乳液中生成非常均匀的胶囊。关于这一过程的机制有一些假设，但缺乏分子水平的详细数据。在项目开始时，将借助各种表征方法(1H-、13C-、29Si-核磁共振、拉曼、红外光谱、SAXS/WAXS、透射电子显微镜、扫描电子显微镜)和分子动力学建模，对二氧化硅颗粒和胶囊的形成机理进行研究。SAXS/WAXS将发挥关键作用，因为在初步工作中，可以获得有关染料分子排列以及界面上无机颗粒的结构信息。这些应加以改进，并与同步加速器上的随时间变化的测量相结合，以收集有关溶胶-凝胶过程动力学的重要数据。通过所获得的信息，这一概念将扩展为一个通用平台。将进行粒子表面的共聚和后功能化。温和的反应条件(pH约为7，没有其他添加剂)也应允许使用敏感的表面修饰剂，如多肽或蛋白质。由于界面处的反应，预期会出现具有Janus形态的粒子。此外，核壳形态和胶体应该可以通过这一过程获得。此外，还计划用含钛单体取代二氧化硅前驱体，以获得细小而均匀的二氧化钛纳米颗粒。由于前驱体的水解性不稳定，可能有必要求助于非水体系。与传统表面活性剂相比，这种染料的一个显着优势是，前者可以很容易地通过洗涤去除，随后在视觉上或光谱上都没有问题。从方法论的观点来看，该项目将重点放在静态光散射实验上。它们将有助于阐明纳米颗粒和胶囊的形成机理，而无需费力的样品制备，并(在线)控制它们的形成过程。该项目侧重于新材料的合成，并提供强有力的方法支持，以便更好地理解和控制合成。材料的选择取决于应用方面，但应用的直接实现将超出项目的范围。项目集中在三个关键问题上：1)染料稳定的机理，2)染料在溶胶-凝胶过程中的作用，3)将这一概念扩展到更多的形态和材料。综上所述，该项目将展示染料稳定的纳米乳液作为溶胶-凝胶过程的界面反应的多功能性、灵活性和高潜力。