Novel Methodology To Control the Adsorption Structure of Cationic Porphyrins on the Clay Surface Using the "Size-Matching Rule"
Novel Methodology To Control the Adsorption Structure of Cationic Porphyrins on the Clay Surface Using the "Size-Matching Rule"
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DOI：
10.1021/la202231k
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发表时间：
2011-09-06
期刊：
影响因子：
3.9
通讯作者：
Takagi, Shinsuke
中科院分区：
文献类型：
--
作者：
Egawa, Tsuyoshi;Watanabe, Hajime;Takagi, Shinsuke
采用水热法合成了具有不同阳离子交换容量的皂石型染料。通过X射线衍射、X射线荧光、Al-27 NMR、FT-IR、热重和差热分析、原子力显微镜和阳离子交换容量测试等手段对材料的结构和性能进行了分析。合成皂石（SS）表面上的电荷间距计算为0.8-1.9 nm的基础上的六方阵列。研究了SS与阳离子卟啉配合物的形成行为。结果表明，卟啉分子在SS表面上的平均分子间距离可以控制，这取决于SS的电荷密度。在四（1-甲基吡啶鎓-4-基）卟啉（H2 TMPyP 4+）的情况下，SS表面上的平均分子间距离可以基于六边形阵列控制在2.3至3.0nm。研究还发现，卟啉的最大吸收值依赖于SS的电荷密度。卟啉在SS表面的吸附行为可以用先前报道的“尺寸匹配规则”合理地解释。该方法利用主体-客体相互作用实现了卟啉分子在SS表面的独特吸附结构控制，其中客体卟啉分子之间的差距距离相当大。这些发现对于构建光化学反应体系如复合物中的能量传递等具有重要的参考价值。
Saponite-type days that have different cation exchange capacities were successfully synthesized by hydrothermal synthesis. The structure and properties were analyzed by X-ray diffraction, X-ray fluorescence, Al-27 NMR, FT-IR, thermo-gravimetric and differential thermal analysis, atomic force microscopy, and cation exchange capacity measurement. The inter-charge distances on the synthetic saponite (SS) surfaces were calculated to be 0.8-1.9 nm on the basis of a hexagonal array. The complex formation behavior between SS and cationic porphyrins was examined. It turns out that the average intermolecular distance between porphyrin molecules on the SS surface can be controlled, depending on the charge density of the SS. In the case of tetrakis(1-methylpyridinium-4-yl)porphyrin (H2TMPyP4+), the average intermolecular distances on the SS surface can be controlled from 2.3 to 3.0 nm on the basis of a hexagonal array. It was also found that absorption maxima of porphyrins depend on the charge density of the SS. The adsorption behavior of porphyrin on the SS surface can be rationally understood by the previously reported "size-matching rule". This methodology using host-guest interaction can realize a unique adsorption structure control of the porphyrin molecule on the SS surface, where the gap distance between guest porphyrin molecules is rather large. These findings will be highly valuable to construct photochemical reaction systems such as energy transfer in the complexes.