暴露金属部位在MOF中的储存中的作用
Jenny G Vitillo1, Laura Regli, Sachin Chavan
1Dipartimento di Chimica IFM and NIS Centre of Excellence, Università di Torino, Via Pietro Giuria 7, 10125 Torino, Italy.
Journal of the American Chemical Society
|June 7, 2008
概括
在金属有机框架 (MOF) 中暴露的金属部位增强了H2的储存. CPO-27-Ni显示了最高的吸附度,但高压储存取决于表面积和孔积.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 金属有机框架 (MOF) 对储存具有前景.
- 在储存的MOF中暴露金属位点的作用尚未完全理解.
- 研究金属位点可访问性对H2吸附的影响对于开发高效的储存材料至关重要.
研究的目的:
- 调查暴露金属部位对MOF中的储性能的影响.
- 为了将被吸附的H2的光谱特征与吸附和H-H延伸频率变化相关联.
- 为了评估不同金属部位暴露的MOF,以评估它们的H2储存能力.
主要方法:
- 红外 (IR) 光谱法用于研究H2吸附.
- 分析了三个MOF:MOF-5 (未暴露的部位),HKUST-1 (Cu2+) 部位和CPO-27-Ni (Ni2+) 部位.
- 使用可变温度IR (VTIR) 方法来确定吸附度.
主要成果:
- 在H2光谱特征的开始温度和吸附热量之间发现了相关性.
- H-H 拉伸频率转移也与吸附度相关,表明金属位点的性质和可访问性的差异.
- 在研究的MOF中,CPO-27-Ni的初始吸附度是最高的 (-13.5 kJ mol(-1)) .
- 在高压下,储能能力主要取决于表面积和孔径.
结论:
- 金属位点的性质和可访问性显著影响H2吸附和光谱指标.
- 虽然CPO-27-Ni具有出色的能量性能,但在高压下整体的H2储存受到表面积和孔积等物理性质的控制.
- 通过物理吸收优化H2储存需要增加MOF中强吸附点的表面密度.
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