Spectral properties, formation of dye molecular aggregates, and reactions in rhodamine 6G/layered silicate dispersions
Spectral properties, formation of dye molecular aggregates, and reactions in rhodamine 6G/layered silicate dispersions
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DOI：
10.1021/jp037607x
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发表时间：
2004-04-08
影响因子：
3.3
通讯作者：
Sasai, R
中科院分区：
文献类型：
--
作者：
Bujdák, J;Iyi, N;Sasai, R
采用锂离子固定的标准方法，以蒙脱石为原料制备了一系列具有系统改性电荷的层状硅酸盐。测试了所制备材料的电荷对吸附阳离子染料罗丹明6 G的光学性质的影响。硅酸盐基底的层电荷控制染料分子组装体的形成，例如H-二聚体和H-和J-聚集体。染料种类（单体，聚集体）的特征在于明显不同的光学性质。紫外/可见和荧光光谱用于表征所研究的系统。时间差光谱应用于调查的反应，进行分散体混合后的染料溶液与硅酸盐。这些反应包括在高电荷密度表面上形成高级聚集体或在中等或低电荷密度表面上的染料解聚集反应。R6 G聚集的一些趋势和特征以及与层电荷有关的随时间的变化与在较早的研究中观察到的其他染料的趋势和特征不同。这可能是由于R6 G阳离子的复杂结构和特定形状。
A series of layered silicates with a systematically modified charge was prepared from montmorillonite, using the standard method of Li+ cation fixation. The effect of the charge of the prepared materials on the optical properties of the adsorbed cationic dye, Rhodamine 6G, was tested. The layer charge of the silicate substrate controlled the formation of the dye's molecular assemblies, such as H-dimers and H- and J-aggregates. The dye species (monomers, aggregates) were characterized by distinctly different optical properties. Ultraviolet/ visible and fluorescence spectroscopies were used for the characterization of the studied systems. Time difference spectroscopy was applied for the investigation of the reactions, which proceeded in dispersions after mixing the dye solution with silicate. The reactions included the formation of higher order aggregates at the surfaces of the high charge densities or dye deaggregation reactions at the surfaces of medium or low charge densities. Some trends and features of the R6G aggregation and the changes with time in relation to the layer charge are different from those that have been observed for other dyes in older studies. This may be due to the complicated structure and the specific shape of the R6G cation.