相关实验视频
Updated: Feb 27, 2026

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Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
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在M1/8Pr5/8MoO4 (M=Li,Na,K) 石岩的不相称的调制结构.
Vladimir A Morozov1, Dina V Deyneko1, Darya G Filatova1
1Chemistry Department, Moscow State University, 119991, Russian Federation.
概括
研究了 scheelite 类型框架 (M1/8Pr5/8□1/4MoO4) 中的阳离子排序. 阴离子和空位的排序影响了晶体结构和MoO四面体几何.
科学领域:
- 固态化学 固态化学
- 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:
- 舍利特型框架以其多功能应用而闻名.
- 了解电离子排序和空隙分布对于调整材料特性至关重要.
- 之前的研究已经探索了各种替代物,但对阴离子缺乏相的详细结构分析仍然是一个活跃的领域.
研究的目的:
- 调查子替代 (Li,Na,K) 对M+/Pr3+子的排序和 scheelite类型结构中的空缺的影响.
- 为了阐明M1/8Pr5/8□1/4MoO4阶段的不相称调制的晶体结构.
- 了解阴子排序,结构调制和构成多面体的几何之间的关系.
主要方法:
- 通过固态反应合成缺M1/8Pr5/8□1/4MoO4 (M = Li,Na,K) 阶段.
- 使用感应合等离子体质谱学 (ICP-MS),感应合等离子体光学发射谱学 (ICP-OES) 和总反射X射线光学 (TXRF) 谱学进行化学表征.
- 使用同步粉X射线衍射 (SPXRD) 数据和瑞特维尔德精炼的结构分析.
- 使用能量分散式X射线光谱法 (EDX) 进行局部元素分布分析.
主要成果:
- 在M1/8Pr5/8MoO4 (M = Li,Na) 中观察到不完全排序的阴子排列,由连续职业调制函数描述,M/Pr和Li/Na原子之间具有反相关系.
- 在K1/8Pr5/8MoO4中,K和Pration的排序是通过crenel函数近似的,其精细组成是K0.145Pr0.618MoO4.
- 所有研究阶段的结构调制都来自于母板结构的A子网格上的M/Prcation和空缺的排序.
- MoO42-四面体的几何表现出灵活性,Mo-O键距离和O-Mo-O键角的显著变化受到A位点群体的影响.
结论:
- 阴离子的排序和空位的分布显著地影响了岩类化合物的调制晶体结构.
- 观察到的排序模式 (连续函数与形函数) 取决于特定的M+离子.
- 摩四面体的灵活性适应了A位点离子大小的变化,突出了这个框架的适应性.
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