DeepMixing – Quantification of the mixing and interfacial hetero-characteristics of nanoparticle aggregates forming in an aerosol mixing zone

DeepMishing â 定量气溶胶混合区中形成的纳米粒子聚集体的混合和界面异质特性

• 批准号: 462260834
• 负责人: Professor Dr.-Ing. Lutz Mädler
• 金额: --
• 依托单位: Fachgebiet Mechanische Verfahrenstechnik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/462260834?language=en
• 关键词: DeepMixing; Quantification; mixing; interfacial; hetero

Functional hetero-contacts between two different nanomaterials are required in various applications including gas sensors, catalysis and batteries to achieve efficient transport processes across the interfaces. In this project, the preparation and formulation of hetero-contacts in the gas phase is realized through the combination of two nanoparticle aggregate producing flames in a double flame spray pyrolysis (DFSP) setup.The product functionality depends on the degree of mixing that determines the number of hetero-contacts and on the hetero-contact quality. The hetero-contact quality significantly depends on the contact area and on the atomic structure of the interface including lattice strain and defect chemistry, if interfacial transport processes govern the functionality. The variation of DFSP process parameters enables the adjustment of the mixing process and resulted in improved functionalities in various applications. However, the characterization of the hetero-contacts on the aggregate and particle scale is far from understood, where the small size of the primary particles of about 10 nm requires the use of transmission electron microscopy (TEM) imaging to achieve a sufficient resolution of the structures. Therefore, the characterization and quantification of the mixture state of aggregates with hetero-contacts are investigated in this project, where the term mixture state explicitly includes the degree of mixing and the contact quality. We apply (S)TEM as indirect method (2D projection of 3D aggregate) using a SPECTRA 300 microscope with a corrector of the spherical aberration of the probe forming lens. The resolution in the STEM mode is 50 pm allowing to study the structural quality of interfaces on an atomic scale. The machine is equipped with a modern silicon drift EDX detector for acquisition of 2D elemental maps, an analytical tomography holder and an on-axis 360° rotation tomography holder. This holder allows reconstruction of composition distribution in 3D for our direct characterization method. We will develop and investigate an automated evaluation of mixture states based on supervised machine learning algorithms, where required training datasets (>100.000 images) consist of synthetic (computer generated) 3D aggregates with defined mixture states providing the ground truth. The parallel method development for tomographic reconstructions of the aggregates will provide the experimental 3D validation of aggregate structures and the mixture states and enable the detailed investigation of the 3D hetero-contact interfaces in the atomistic level.

气体传感器、催化和电池等各种应用都需要两种不同纳米材料之间的功能性异质接触，以实现跨界面的有效传输过程。在该项目中，通过组合实现了气相异质接触的制备和配制。两种纳米颗粒聚集体在双火焰喷雾热解 (DFSP) 设置中产生火焰。产品功能取决于决定异质接触数量的混合程度以及异质接触质量。如果界面传输过程控制功能，则异质接触的质量很大程度上取决于接触面积和界面的原子结构，包括晶格应变和缺陷化学。DFSP 工艺参数的变化能够调整混合过程并导致。然而，异质接触在聚集体和颗粒尺度上的表征还远未被了解，其中初级颗粒尺寸约为 10 nm，需要使用透射电子显微镜 (TEM)。因此，本项目研究了具有异质接触的聚集体的混合状态的表征和量化，其中术语“混合状态”明确包括混合程度和接触质量。 (S)TEM 作为间接方法（3D 聚合体的 2D 投影），使用带有探针形成透镜球面像差校正器的 SPECTRA 300 显微镜，STEM 模式下的分辨率为 50 pm，允许研究。该机器配备了用于采集 2D 元素图的现代硅漂移 EDX 探测器、分析断层扫描支架和轴上 360° 旋转断层扫描支架。该支架可以重建成分分布。我们将开发和研究基于监督机器学习算法的混合状态的自动评估，其中所需的训练数据集（> 100.000 个图像）由合成（计算机）组成。具有定义的混合状态的 3D 聚集体提供了基本事实，用于聚集体断层扫描重建的并行方法开发将提供聚集体结构和混合状态的实验 3D 验证，并能够对 3D 异质接触界面进行详细研究。原子级别。