在石结晶过程中,反应动力学调节无形矩阵中短距离秩序的形成
Ching-Tien Chen1, Kenta Iyoki1, Peidong Hu1,2
1Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|July 16, 2021
概括
了解石结晶需要检查无形矩阵的形成. 反应剂的选择和凝结动力学对短距离的顺序产生了关键影响,影响了化石核化频率和合成.
科学领域:
- 材料科学
- 化学学
- 晶体学
背景情况:
- 由于观察无形矩阵内核的困难,特别是密集的水凝中,石结晶,即变异为顺序的变化,是很难理解的.
- 合成条件,无形物种和石结晶行为之间的关系尚不清楚.
研究的目的:
- 通过使用不同的反应剂在密集的水凝系统中研究酸矩阵的结构演变.
- 阐明反应物的反应性和凝结动力学在无形矩阵形成和随后的热核形成中的关键作用.
主要方法:
- 在密集的水凝系统中对结构演化的比较研究,使用蒸与溶液作为Si反应剂.
- 在不同反应条件下 (温度,老化) 分析无形矩阵的形成和结构特征.
主要成果:
- 蒸二氧化在80°C的温度下与酸逐渐反应,产生一种无形固体,具有富含Al的四个成员和富含Si的六个成员环,促进了酸X (FAU) 构建单元的形成.
- 与酸盐和酸发生了即时,强烈的凝结,形成了一个稳定,复杂的矩阵,阻碍了结晶.
- 在加热之前在环境温度下老化反应剂混合物促进了短距离的顺序,增加了热核的频率.
结论:
- 反应剂选择和凝结动力学对于无形矩阵内有序的短距离结构的形成至关重要,直接影响着热石核形成.
- 在无形前体中控制特定环结构的形成是高效的化X (FAU) 结晶的关键.
- 优化衰老和反应条件可以增强有序无形结构的形成,从而增加石核化频率.
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