节点连接器连接对 - 铁甲酸协调聚合物的放射性稳定性的影响
Zoë C Emory1, Heather J Culbertson1, Cale B Gaster1
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame 46556, Indiana, United States.
Inorganic chemistry
|April 24, 2025
概括
甲甲甲酸盐金属有机框架 (MOFs) 的辐射稳定性进行了测试. Th(BDC) 2表现出异常的抗性,表明独特的节点链接器连接在电离辐射下增强了MOF的耐用性.
科学领域:
- 材料科学 材料科学 材料科学
- 核工程 核工程是指核工程.
- 放射化学 放射化学是指辐射化学.
背景情况:
- 金属有机框架 (MOFs) 具有高孔隙性和可调节性,使其适用于核燃料循环应用.
- 在高辐射环境中,MOF的辐射稳定性至关重要,需要对影响耐用性的结构因素进行研究.
- 之前的研究对MOF组件进行了变化;这项工作保持了一致的金属和链接元件,以隔离对辐射抵抗的结构影响.
研究的目的:
- 为了确定增强基MOF辐射稳定的结构特征.
- 为了评估在离子辐射下特定的 - 铁甲酸盐混合材料的辐射抵抗.
- 为了确定MOF结构和在电离辐射下性能之间的相关性.
主要方法:
- 研究了Th(BDC) 2 ((DMF) 2 ,Th(BDC) 2和Th-UiO-66的辐射抵抗,使用离子辐射高达227MGy.
- 通过粉末X射线衍射 (PXRD),扩散反射红外里埃变换光谱 (DRIFTS) 和密度函数理论 (DFT) 计算来评估结构稳定性.
- 对不同MOF结构的量化辐射稳定性值.
主要成果:
- BDC) 2表现出优越的辐射稳定性,在最高剂量下表现优于BDC) 2DMF) 2和-UiO-66.
- 辐射稳定性顺序被确定为Th(BDC) 2>Th(BDC) 2>DMF) 2>Th-UiO-66.
- 在Th(BDC) 2 ((DMF) 2中存在的二甲基形式胺 (DMF) 提高了辐射耐受性,很可能是因为它作为牺牲性连接体.
结论:
- 独特的节点-链接器连接和较短的连接器间距离有助于增强MOF中的放射性稳定性.
- 结构设计,包括连接体选择和连接性,对于开发用于核应用的辐射硬化MOF至关重要.
- BDC) 2为核燃料循环提供了一个高度辐射稳定的MOF候选物.
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