Synthesis of Composite Particles by Liquid Aerosol Thermolysis

液体气溶胶热解合成复合颗粒

• 批准号: 9202418
• 负责人: Gary Messing
• 金额: $ 31.35万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9202418&HistoricalAwards=false
• 关键词: Synthesis; Composite; Particles; Liquid; Aerosol

Liquid aerosol thermolysis (LAT) refers to the general class of particle synthesis processes in which a liquid precursor solution is atomized into discrete droplets and subsequently transported through a time/temperature/atmosphere-regulated reactor. The overall objective of the proposed program is to establish a fundamental engineering science for the synthesis of submicron, composite particles by liquid aerosol thermolysis. Particle synthesis and solution experiments are designed to identify those factors affecting solid composite particle formation and chemical distribution. In situ technique will be used to monitor droplets generation and shrinkage during the evaporation stage as a function of atomization, precursor solution characteristics and evaporation conditions. After the evaporation stage, on-line sampling will be used to obtain and characterize particles as a function of time and temperature. Each process step will be mathematically analyzed using information generated in the above experiments and evaluated against existing or derived models for those processes. Model systems, based on alumina precursors as the matrix phase, have been selected examine first the synthesis of homogeneous composite systems in which the nanocrystalline phases are uniformly dispersed and second, those in which one phase encapsulates the other. Zinconia and platinum in alumina allow use to examine issues associated with uniform precipitation whereas alumina-SiC allows us the possibility to examine the isolation of one phase (SiC) within another (i.e. intragranular). The proposed techniques aim to production of nanocrystalline materials of a wide compositional range and having 100 nm crystallinity, of desired uniformity and second phase distribution.

液体气溶胶热解（LAT）是指将液体前体溶液雾化为离散液滴的一般粒子合成过程，然后通过时间/温度/大气调节的反应器运输。 拟议程序的总体目标是建立一门基本的工程科学，用于通过液体气溶胶热解的合成亚微米，复合颗粒。 粒子合成和溶液实验旨在识别影响固体复合颗粒形成和化学分布的因素。 原位技术将用于监测蒸发阶段的液滴的产生和收缩，这是雾化，前体溶液特征和蒸发条件的函数。 蒸发阶段之后，将使用在线抽样来获取和表征粒子作为时间和温度的函数。 每个过程步骤将使用上述实验中生成的信息数学分析，并针对这些过程的现有或派生模型进行评估。 首先选择了基于氧化铝前体作为基质相的模型系统，首先检查了均匀的复合系统的合成，其中纳米晶相位均匀分散，其次是一个阶段，其中一个相封装了另一个相。 氧化铝中的Zinconia和Platinum可以用来检查与均匀降水有关的问题，而氧化铝-SIC使我们有可能检查在另一个相（即刻内）中的一个相（SIC）的分离。 该提出的技术旨在生产具有较大组成范围的纳米晶体材料，并且具有100 nm的结晶度，具有所需的均匀性和第二相分布。