氧化多态性对等离子体合成条件的依赖性
Emily N Weerakkody1, Batikan Koroglu1, Zurong Dai1
1Physical and Life Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.
The journal of physical chemistry. A
|March 14, 2024
概括
在等离子流反应器中合成的氧化纳米颗粒显示出不同的相 (UO2和UO3). 粒子组成不受收集参数的影响,但冷却历史影响了UO2/UO3比率和大小.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 等离子体物理学的物理学
背景情况:
- 氧化纳米粒子对于核应用至关重要.
- 控制纳米粒子合成参数是定制材料特性的关键.
研究的目的:
- 研究血流反应器 (PFR) 合成参数对氧化纳米粒子形态和物种的影响.
- 了解收集时间,基板温度和辐射位置如何影响粒子特征.
- 分析不同气体流速对粒子温度历史和由此产生的相的影响.
主要方法:
- 使用等离子流反应器 (PFR) 合成氧化纳米粒子.
- 使用传输电子显微镜 (TEM) 进行粒子形态学和物种化的表征.
- 收集时间,基质温度和辐射位置的系统变化.
- 通过下游气体流量调整操纵轴向温度配置.
主要成果:
- 确定了两个氧化相,面中心立方 (fcc) -UO2和α-UO3.
- 颗粒的化学成分与收集时间,基质温度和辐射位置无关.
- 采集基板的预热减少了颗粒沉积,这是由于降低了热泳力.
- UO2与UO3的比率和颗粒大小受到合成过程中冷却历史的显著影响.
结论:
- 流反应堆合成允许形成不同的氧化相.
- 虽然收集参数不会改变化学成分,但热史对于控制纳米粒子物种化和大小至关重要.
- 了解这些合成结构关系对于优化氧化物纳米颗粒生产用于特定应用至关重要.
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