Reacting precursor/solvent microdroplets in confined 2-D microflows for tailored nanomaterials synthesis

在受限的二维微流中反应前体/溶剂微滴，以合成定制的纳米材料

• 批准号: 509113367
• 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: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/509113367?language=en
• 关键词: Reacting; precursor; solvent; microdroplets; confined

Flame spray pyrolysis (FSP) is a robust technique that can synthesize chemically complex particles via aerosol combustion of precursor/solvent droplets. The burning microdroplets themselves can be regarded as spatially-confined microreactors, with numerous mechanistic pathways involved in realizing the final product size, composition, and morphology. The key idea of our work is to go beyond conventional FSP, and to further confine the burning microdroplets within a Hele-Shaw cell, creating a novel arrangement of microreactors within a microreactor. Such a device not only offers precise fundamental investigation of the variations in chemical properties and physical dynamics for initially same-sized burning droplets affected by confinement in one-dimension, but also affords the definition of the reaction environment with specific parameter histories for single microdroplets to design nanoparticles of tailored chemical composition and crystal structure, in scalable, uniform, and consistent fashion. The objective of the proposed program focuses on investigating the mechanisms of droplet-to-particle conversion and gas-to-particle conversion in a confined environment by utilizing a reactive multiphase 2D microflow system with controlled individual burning liquid precursor/solvent droplets in precisely adjustable environments. Such ability to define process conditions along a microdroplet’s path should allow unparalleled ability to fabricate high-quality and tailored nanoparticles in a continuous system whose output can be directed into another system for inline processing of composite materials or for other uses. The microdroplet reactor can attain large heating and cooling rates, affecting detailed chemistry and transport in far-from-equilibrium conditions. Individual droplet investigation can be conducted using temperature-controlled (heated or cooled) walls to sustain combustion or quench reactions, where the droplets and as-produced nanomaterials can be characterized (e.g., offline using chromatography by sampling) at different locations (correlating to different residence times), thereby measuring reaction kinetics and nanomaterials evolution. Burning droplets can coalesce with burning/non-burning droplets of same or different precursors. The setup is amenable to a host of in-situ diagnostics, including laser-based spectroscopy, high-speed imaging, interferometric particle imaging, and rainbow refractometry. Ex-situ characterization and computational modelling will be conducted to understand, optimize, and guide the experiments. The team of Mädler and Tse have the unique multidisciplinary expertise consisting of combustion, materials synthesis, theoretical and numerical modeling, process engineering, and advanced characterization techniques, along with previous joint work, to address the proposed work.

火焰喷雾热解（FSP）是一种强大的技术，可以通过前体/溶剂液滴的气溶胶燃烧来合成化学复杂的颗粒，燃烧的微滴本身可以被视为空间受限的微反应器，涉及实现最终产品尺寸的许多机械途径。我们工作的关键思想是超越传统的 FSP，并进一步将燃烧的微滴限制在 Hele-Shaw 池内，创造出一种新颖的微反应器排列。这种装置不仅可以对受一维约束影响的初始相同大小的燃烧液滴的化学性质和物理动力学变化进行精确的基础研究，而且还可以定义具有特定参数历史的反应环境。针对单个微滴，以可扩展、均匀和一致的方式设计具有定制化学成分和晶体结构的纳米颗粒。该项目的目标重点是研究液滴到颗粒转化和气体到颗粒转化的机制。通过利用反应性多相 2D 微流系统在精确可调节的环境中控制单独燃烧的液体前体/溶剂液滴，这种沿着微滴路径定义工艺条件的能力应该允许在连续系统中制造高质量和定制的纳米颗粒的无与伦比的能力。其输出可以直接进入另一个系统，用于复合材料的在线处理或用于其他用途。微滴反应器可以实现较大的加热和冷却速率，从而影响远非平衡条件下的详细化学反应和传输。可以使用温度控制（加热或冷却）的壁来维持燃烧或淬火反应来进行单个液滴研究，其中可以在不同位置（与不同的位置相关）对液滴和所产生的纳米材料进行表征（例如，通过采样进行离线色谱分析）停留时间），从而测量反应动力学和纳米材料的演化，燃烧液滴可以与相同或不同前体的燃烧/非燃烧液滴聚结。 Mädler 和 Tse 团队将进行原位诊断，包括基于激光的光谱、高速成像、干涉粒子成像和彩虹折射测量。拥有独特的多学科专业知识，包括燃烧、材料合成、理论和数值建模、过程工程和先进的表征技术，以及之前的联合工作，以解决拟议的工作。