Online assessment of the crystalline modification of nanoparticles in the gas phase

纳米粒子在气相中的结晶改性的在线评估

• 批准号: 310472725
• 负责人: Professor Dr.-Ing. Andreas Bräuer
• 金额: --
• 依托单位: Institut für Thermische Verfahrenstechnik, Umwelt- und Naturstoffverfahrenstechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/310472725?language=en
• 关键词: Online; assessment; crystalline; modification; nanoparticles

The synthesis of nanoparticles from the gas phase is resource-efficient and common. Thanks to cause and effect studies, it is known that particle properties (size, morphology, degree of agglomeration, crystallinity) can be changed by a variation of process parameters. Presently, the properties of the synthesized particles are characterized offline with considerable time delay after sample extraction and preparation, thus yielding only scarce information about the process-to-product event chain and not allowing direct influence on it. Within the second funding phase of the DFG/AIF joint project - Multi parameter characterization of particle based functional materials by means of innovative online measurement systems (MPaC) - , hereby an online and in-situ method of measurement for the analysis of the CRYSTALLINITY of particles in the gas phase is to be developed and tested in a new sub-project. The crystallinity as an internal structural parameter of particles has enormous relevance for the means of application, such as the bioavailability of active agents or the conductivity of particles. With this project, the hitherto not covered aspect of the parameter CRYSTALLINITY complements the works for the analysis of morphology, size and structure of the other MPaC sub-projects. Aim of this project is the development of a new Raman measurement process for the online and in-situ assessment of the crystalline modification of nanoparticles in the gas phase, with the simultaneous analysis of the gas phase temperature and composition. This allows investigating into the influence of varied process parameters on the resulting product properties in corresponding gas phase particle processes. By means of Raman spectroscopy, it is possible to distinguish polymorphs in aerosols by their characteristic spectral signatures. Simultaneously the gas phase temperature is ascertained from the rotational Raman spectrum of nitrogen. Due to the relatively weak cross-section of Raman scattering compared to concurring light-matter interactions, particular attention is paid to the efficient excitation and detection of the Raman signals, at the same time minimizing concurring and interfering disturbing signals (chemiluminescence, fluorescence). This will be realized by optimizing and building up a custom-made spectrometer especially for this project, and the application of the Shifted Excitation Raman Difference Spectroscopy (SERDS) method. The measurement method will be developed on the basis of the particle systems Titanium dioxide, Zirconium dioxide, and Iron(III) oxide dispersed in the gas phase.

从气相合成纳米颗粒是一种资源高效且普遍的方法。由于因果关系的研究，我们知道颗粒的性质（大小、形态、团聚程度、结晶度）可以通过工艺参数的变化而改变。目前，合成粒子的性质是离线表征的，在样品提取和制备后有相当长的时间延迟，因此只能获得关于过程到产品事件链的稀缺信息，并且不能直接影响它。在DFG/AIF联合项目的第二个资助阶段-利用创新的在线测量系统（MPaC）对颗粒基功能材料进行多参数表征-在此，一种用于分析气相颗粒结晶度的在线和原位测量方法将在一个新的子项目中开发和测试。结晶度作为颗粒的内部结构参数，对诸如活性剂的生物利用度或颗粒的导电性等应用手段具有巨大的相关性。在这个项目中，迄今为止尚未涉及的参数结晶性方面补充了其他MPaC子项目的形态、大小和结构分析工作。该项目的目的是开发一种新的拉曼测量方法，用于在线和现场评估纳米颗粒在气相中的晶体修饰，同时分析气相温度和成分。这允许研究不同工艺参数对相应气相颗粒工艺中所得产品性能的影响。利用拉曼光谱，可以通过气溶胶的特征光谱特征来区分多晶态。同时利用氮的旋转拉曼光谱确定了气相温度。由于拉曼散射的横截面相对于光-物质共发生相互作用而言相对较弱，因此特别关注拉曼信号的有效激发和检测，同时尽量减少共发生和干扰的干扰信号（化学发光，荧光）。这将通过优化和建造专门为该项目定制的光谱仪，以及应用位移激发拉曼差分光谱（SERDS）方法来实现。测量方法将基于分散在气相中的二氧化钛，二氧化锆和氧化铁（III）颗粒系统开发。