在脱水的普鲁士蓝色类似物M3[Co(CN) [6]2 (M = Mn, Fe, Co, Ni, Cu, Zn) 中储存
Steven S Kaye1, Jeffrey R Long
1Department of Chemistry, University of California, Berkeley, CA 94720-1460, USA.
Journal of the American Chemical Society
|May 5, 2005
概括
普鲁士蓝色类似物具有较大的表面积和显著的储能. 这些材料在高效的吸附和储存应用中显示出有前途的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 纳米技术 纳米技术
背景情况:
- 普鲁士蓝的类似物是具有可调节结构的协调化合物.
- 高效的存材料对于清洁能源技术至关重要.
- 了解孔隙性和吸附性质是材料设计的关键.
研究的目的:
- 为了研究脱水的普鲁士蓝色类似物M3[Co(CN) 6的多孔性和储性质.
- 评估这些材料在冷温度下吸附的潜力.
- 为了确定材料组成和吸收之间的关系.
主要方法:
- 合成了六种普鲁士蓝色类似物:M3[Co(CN) 6 2 (M = Mn,Fe,Co,Ni,Cu,Zn).它们的合成方法是:
- 在87K处使用吸异热体来确定BET表面积.
- 在77 K和890 Torr的吸附同热器测量储能容量.
- 对于最大吸收预测的Langmuir-Freundlich方程的适配.
- 在77K和87K的同热体中计算吸附热量.
主要成果:
- BET的表面积从560 m2/g (Ni) 到870 m2/g (Mn) 之间,Mn3[Co(CN) 6]2与热石相似.
- 观察到大量的吸附,容量高达1.8%的重量%和0.025千克的H2/L (Cu).
- 预测和能力为Cu3[Co(CN) 6达到2.1重量%和0.029公斤H2/L.
- 吸附度随着M的增加而增加,以Mn < Zn < Fe < Co < Cu < Ni的顺序,在5.3-7.4kJ/mol之间.
结论:
- 脱水的普鲁士蓝色类似物具有较高的表面积和大量的储存能力.
- 与基准金属有机框架相比,研究的材料显示出更高的结合度.
- 这些发现突出了普鲁士蓝色类似物作为先进储存解决方案的有希望的候选者.
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