具有不同微观结构的CaTiO3空心晶体的形成机制
Xianfeng Yang1, Junxiang Fu, Chongjun Jin
1State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, and Instrumental Analysis and Research Centre, Sun Yat-Sen (Zhongshan) University, Guangzhou 510275, PR China.
Journal of the American Chemical Society
|September 17, 2010
概括
研究人员探索了酸 (CaTiO(3)) 空洞晶体的形成. 聚乙烯糖醇溶液中受控的水含量引导自我组装和奥斯瓦尔德成熟,产生可调节的空心晶体微观结构.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体的成长 晶体的成长
- 陶工程 陶工程
背景情况:
- 酸 (CaTiO(3)) 是一种具有多样化应用的矿材料.
- 控制陶材料的微观结构对于优化其性能至关重要.
- 空洞晶体结构在各种领域提供了独特的优势.
研究的目的:
- 为了研究CaTiO的晶体生长(3) 具有受控微观结构的空心晶体.
- 了解聚乙烯糖醇 (PEG-200) 和水含量在形成过程中的作用.
- 为了确定陶材料的反向晶体生长路径.
主要方法:
- 在无水PEG-200溶液中合成CaTiO(3) 纳米立方体.
- 观察纳米立方体的定向自我组装成球形粒子.
- 诱导奥斯瓦尔德成熟形成空洞球体.
- 控制添加水来修改表面再结晶和形态.
主要成果:
- 聚合并组装成球体的CaTiO(3) 纳米立方体,外中的更大的纳米立方体.
- 奥斯瓦德的成熟导致球形空洞晶体的形成.
- 添加水 (1.25体积%) 促进了表面再结晶,形成立方体形态.
- 较高的水含量 (5体积%) 导致单晶空心立方体.
- 在CaTiO(3) 的ortorhombic扭曲没有显著影响纳米立方体聚合.
结论:
- 提出了一个反向的晶体生长机制,涉及聚合,表面结晶和表面到核心再结晶.
- 该研究展示了一种控制CaTiO(3) 空洞晶体微结构的方法.
- 这些发现为其他空心陶晶体的形成提供了洞察力.
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