通过动力学有效的辅助转化反应选择性形成氧化物
Paul K Todd1, James R Neilson1
1Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523-1872 , United States.
Journal of the American Chemical Society
|January 10, 2019
概括
使用碳酸盐可以选择性地合成氧化物. 这种方法控制了反应路径,使得在较低的温度下形成特定的氧化物相.
科学领域:
- 材料科学
- 无机化学
- 固态化学
背景情况:
- 复杂的氧化物合成通常需要高温,有利于热力学稳定的阶段.
- 开发动力控制合成方法对于获得转移稳定或新型氧化物结构至关重要.
研究的目的:
- 展示不同氧化物多态的选择性合成.
- 研究金属物种在控制反应路径和产品形成中的作用.
主要方法:
- 有助转化反应涉及 (III) 氧化物 (Mn2O3), (III) 化物 (YCl3) 和金属碳酸盐 (A2CO3,其中A=Li,Na,K).
- 在控制温度下在流动氧气下进行反应.
- 进行了产品表征,以确定产生的氧化物阶段.
主要成果:
- 碳酸盐在550-850°C之间促进了YMnO3 (o-YMnO3+δ) 的形成.
- 在650°C下,碳酸导致化物Y2Mn2O7.
- 碳酸没有产生选择性产物,六边形YMnO3在950°C以上与所有金属形成.
结论:
- 金属物种在修改反应路径和实现对氧化物合成的动力控制方面发挥着关键作用.
- 辅助转化为特定复杂氧化物相的选择性低温合成提供了可行的途径.
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