含有Ce的ABO矿中的状体分解:第二部分,CeCrO3中分离生长的情况
Aaron C Johnston-Peck1, Adam J Biacchi2, Russell A Maier1
1Material Measurement Laboratory National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899 United States.
概括
矿酸盐 (CeCrO) 在加热时发生eutectoid转化,形成二氧化 (CeO2) 和氧化 (CrO3). 由此产生的微观结构缺乏合作增长,与类似的矿转化不同.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 陶制品 在陶方面.
背景情况:
- 矿氧化物是一种多用途的材料类,在催化,电子和能量储存方面具有应用.
- 了解矿的相变化对于控制其性能和性能至关重要.
- 矿结构的状分解为新型材料微观结构提供了一条途径.
研究的目的:
- 在空气中加热时,研究酸盐 (CeCrO3) 的eutectoid相变.
- 阐明反应动力学,产品微观结构和转化机制.
- 将转换行为与其他矿系统进行比较,例如化 (CeAlO).
主要方法:
- 对反应动力学进行热重力测量分析 (TGA).
- 用X射线衍射 (XRD) 和拉曼光谱进行相位识别.
- 电子显微镜 (SEM/TEM) 用于微观结构和形态分析.
主要成果:
- CeCrO3分解成化二氧化物 (CeO2) 和冠状体氧化 (Cr2O3).
- CeO2颗粒具有多孔,多晶的微观结构,具有异型的粒度生长.
- Cr2O3粒子形成为单晶,缺乏与母相的晶体学方向.
结论:
- CeCrO3的形转化产生了一个缺乏合作生长特征的微观结构,与CeAlO3不同.
- 由此产生的氧化物相之间的界面能量差异 (CeO2/Cr2O3与CeO2/Al2O3) 解释了不同的转换行为.
- 这项研究提供了对矿分解产物的结构性质关系的见解.
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