Research Initiation Award: Single Particle Studies of Particle Morphology Evolution During Spray Processing of Inorganic Materials

研究启动奖：无机材料喷涂过程中颗粒形态演化的单颗粒研究

• 批准号: 9409394
• 负责人: Timothy Ward
• 金额: $ 10万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-07-01 至 1997-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9409394&HistoricalAwards=false
• 关键词: Research; Initiation; Award; Single; Particle

ABSTRACT Timothy Ward CTS-9509394 The objectives of this research are: (1) to advance the understanding of the physical and chemical processes which govern the particle morphology (e.g. dense, hollow particles or porous) and microstructure (e.g. find-grained or single crystal) of inorganic (ceramic or metal) powders produced by spray processes, and (2) to utilize that understanding to develop and test strategies for producing desired, or avoiding undesired, morphologies for several representative materials and precursor types. The basic experimental approach will be to utilize an electrodynamic balance to levitate individual solution precursor particles, and then observe the morphology evolution of the individual particle as the temperature and/or humidity are changed in a controlled fashion. As the temperature is changed (up to 800{SYMBOL 176 \f "Symbol"}C or higher in some cases), solvent evaporation, precursor decomposition, gas evolution, melting, sintering, evaporation/condensation and other processes contribute to the final morphology and microstructure. Morphology evolution will be followed visually using a video camera and light scattering, and mass changes will be monitored using a video camera and light scattering, and mass changes will be monitored using the particle levitation voltage. Both single-phase and multicomponent/multiphase particles will be investigated utilizing precursors which have been reported to yield different particle morphologies in powder synthesis by spray pyrolysis. Specifically, metallic Ag and zirconia will be studied using nitrate, chloride, organometallic and colloidal precursors. Metal/ceramic composite particles (zirconia/silver) and multicomponent mixtures containing a volatile component (PbO) will be investigated. The results of this project will enable better control over particle characteristics in materials produced by spray processes. Inorganic materials which might be good candidates for production by spray processes include: elec tronic ceramics such as superconductors and ferroelectrics, fullerenes, nanophase materials and composites, and metal powders. ***

摘要 Timothy Ward CTS-9509394 这项研究的目标是：(1) 增进对控制颗粒形态（例如致密、空心颗粒或多孔）和微观结构（例如细粒或单晶）的物理和化学过程的理解）通过喷涂工艺生产的无机（陶瓷或金属）粉末，以及（2）利用这种理解来开发和测试策略，以生产几种代表性材料所需的或避免不需要的形态和前体类型。 基本的实验方法是利用电动平衡来悬浮各个溶液前体颗粒，然后观察随着温度和/或湿度以受控方式改变时各个颗粒的形态演变。 随着温度的变化（在某些情况下高达 800{SYMBOL 176 \f "Symbol"}C 或更高），溶剂蒸发、前体分解、气体逸出、熔化、烧结、蒸发/冷凝和其他过程有助于最终形态和微观结构。 将使用摄像机和光散射在视觉上跟踪形态演化，并且将使用摄像机和光散射来监测质量变化，并且将使用粒子悬浮电压来监测质量变化。 将利用前体对单相和多组分/多相颗粒进行研究，据报道，通过喷雾热解在粉末合成中可产生不同的颗粒形态。 具体来说，将使用硝酸盐、氯化物、有机金属和胶体前体来研究金属银和氧化锆。 将研究金属/陶瓷复合颗粒（氧化锆/银）和含有挥发性组分（PbO）的多组分混合物。 该项目的结果将能够更好地控制喷涂工艺生产的材料中的颗粒特性。 可能适合通过喷涂工艺生产的无机材料包括：电子陶瓷，例如超导体和铁电体、富勒烯、纳米相材料和复合材料以及金属粉末。 ***