选择性结合 O2 超过 N2 在一个氧化还原活性金属有机框架与开放的铁(II) 协调站点
Eric D Bloch1, Leslie J Murray, Wendy L Queen
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 12, 2011
概括
这项研究提出了一个新的金属有机框架,Fe(2)(dobdc),能够选择性地吸附氧气. 这种材料在更高的温度下显示出高效的空气分离的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 分离科学 分离科学
背景情况:
- 金属有机框架 (MOF) 为气体吸附提供可调节的性能.
- MOF-74/CPO-27型结构以其高表面积和通道状孔隙而闻名.
- 在各种工业应用中,有效地将氧气与空气分离至关重要.
研究的目的:
- 为了合成和描述一个新的Fe(2)(dobdc) 金属有机框架.
- 调查脱框架的气体吸附特性,特别是对O2和N2的吸附特性.
- 探索Fe(2)(dobdc) 在空气分离应用中的潜力.
主要方法:
- 使用FeCl(2) 和H(4) dobdc.使用Fe(2)(dobdc) ·4DMF的无空气合成.
- 溶解以获得多孔的Fe(2)(dobdc) 材料.
- 在298K和211K测量气体吸附同热体.
- 光谱分析 (Mössbauer,IR) 和粉末中子衍射用于结构和电子表征.
- 理想吸附溶液理论 (IAST) 对突破曲线的模拟.
主要成果:
- 二) 合成为MOF-74/CPO-27模拟物,BET表面积为1360 m2 / g.
- 该材料具有高容量 (在298K时9.3%重量%,在211K时18.2%重量%) 的选择性O2吸附,超过N2吸附.
- 光谱和衍射数据表明,在室温下氧化后,Fe (II) 和O (II) 之间发生电荷转移,形成Fe (III) 和O (II) -2.
- 鉴定出O(2) 的结合模式在低温下是对称的侧向,而在氧化时则是侧向的.
结论:
- 铁 (Fe) 是一种用于选择性氧气捕获的高效材料.
- 观察到的可逆O(2) 吸附和电荷转移机制是其性能的关键.
- IAST的模拟表明Fe2是工业高温空气分离的一个有希望的候选者.
相关概念视频
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