六角瓦特利特的形态和结构的发展
Emilie M Pouget1, Paul H H Bomans, Archan Dey
1Laboratory of Materials and Interface Chemistry and Soft Matter CryoTEM Research Unit, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|July 31, 2010
概括
研究人员揭示了无形碳酸如何转化为六角瓦特里特晶体. 氨离子指导这种固态转化,同时开发生物模拟材料的晶体秩序和形态.
科学领域:
- 生物矿物化 生物矿物化
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 生物仿真合成旨在复制复杂的CaCO3结构.
- 添加剂通过选择性抑制晶体面来控制晶体形态.
- 在CaCO(3) 形成过程中,无形转化为晶体的过程尚未完全理解.
研究的目的:
- 为了阐明在瓦特里特形成过程中的无形到晶体的过渡.
- 研究离子在瓦特里特晶体生长中的作用.
- 详细介绍秩序和形态学的同时发展.
主要方法:
- 低温传导电子显微镜 (cryoTEM). 低温传导电子显微镜.
- 技术包括明亮场成像,冷扫描,低剂量电子衍射和冷暗场成像.
- 研究了在NH ((4) ((+)) 离子的存在下瓦特里特晶体的形成.
主要成果:
- 六角瓦特里特通过无形前体阶段形成.
- 无形阶段经历固态转化为晶体瓦特里特.
- 多晶瓦特转变为单一的晶体,由NH(4)(+) 诱导的晶体平面模板.
结论:
- 氨离子指导无形碳酸的固态转化为单晶瓦特里特.
- 在这个仿生过程中,秩序和形态的同时发展是关键.
- 了解这种转变,可以了解生物矿物化和合成晶体生长.
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