氧化物促进拆卸 Zr-Polyoxocations的重新组装
James A Sommers1, Danielle C Hutchison1, Nicolas P Martin1
1Department of Chemistry , Oregon State University , Corvallis , Oregon 97331 , United States.
Journal of the American Chemical Society
|October 1, 2019
概括
研究人员通过将过氧化物添加到氧酸盐溶液中,发现了两种新的/哈夫集群拓. 这些新型聚合物,Zr5和Zr4,扩展了无机纳米光刻和催化应用的已知结构.
科学领域:
- 无机化学
- 材料科学
- 纳米技术
背景情况:
- /哈夫 (Zr/Hf) 水酸集群对于无机纳米光刻,金属有机框架 (MOF),催化和核燃料再加工等应用至关重要.
- 此前只有两个Zr/Hf集群拓已知,限制了它们的潜在应用.
- 无处不在的正方形多氧化物 (Zr5) 是由Zr/Hf氧盐形成的,但其在酸盐溶液中的结构受到争议.
研究的目的:
- 探索超出之前确定的两个Zr/Hf集群拓.
- 研究过氧化物添加对Zr/Hf氧酸盐溶液的影响.
- 描述Zr/Hf新星团的结构和形成路径.
主要方法:
- 用单晶X射线衍射来确定新形成的星团的精确结构.
- 微角X射线散射 (SAXS) 和对分布函数 (PDF) 分析阐明了水溶液中的形成途径.
- 电喷离子质谱 (ESI-MS) 提供了对集群碎片化和物种化的见解.
主要成果:
- 合成和描述了两个新的Zr/Hf集群拓:Zr5,一个五边形组合 ([Zr25O10(OH) 50(O2) 5(H2O) 40) ((ClO4) 10·xH2O),和Zr4,一个以氧为中心的四面体 ([Zr4OH(4(μ-O2) 2(μ4-O) ((H2O) 12) ((ClO4) 6·xH2O).
- 到目前为止,Zr5是最大的Zr/Hf集群拓,可溶于有机溶剂中.
- 该研究揭示了不寻常的组装机制,包括Zr5从较小的寡合体和过氧化物促进的拆解途径的固态组装.
结论:
- 将过氧化物添加到Zr氧酸盐溶液中成功产生了新的Zr/Hf集群拓,显著扩大了已知的结构多样性.
- 这些集群的形成和拆卸途径受过氧化物度和溶液酸度的影响.
- 这些发现为在各种先进的应用中合成和利用IV组聚合物开辟了新的途径.
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