固气界面上花菁染料J-聚集体的研究

研究固气界面上花菁染料J-聚集体的光学性质、形貌特点和形成机制。以花菁染料为研究对象，在云母基底表面制备花菁染料的超分子J-聚集体，根据J-聚集体独特的光学性能，通过紫外吸收光谱，荧光光谱，荧光显微镜等对云母界面上的花菁染料聚集体进行光谱测量和形貌表征。结果表明：云母／空气界面上的花菁染料聚集体在580nm处出现相对于染料单体红移且狭窄的强吸收峰，而在583nm处出现一个伴随微弱Stokes位移的荧光峰，这些结果符合吸附在基质上的J-聚集体的光学特征，同时荧光显微镜观察表明云母基底上分散分布着2～4μm微晶棒状的聚集体。结果证明：花菁染料能够在云母／空气界面生成超分子J-聚集体，其形成机制是通过带正电荷的花菁染料分子与云母基底表面带负电荷的空穴通过外延相互作用形成的。

Investigation of Pseudoisocyanine Dye J-aggregates at a Solid/Air Interface

J-aggregates of pseudoisocyanine （PIC） dye at a mica/air interface were investigated because of their interesting optical properties. In this study, aggregates of PIC were prepared on a mica base. Absorption spectrum and fluorescence spectrum of the aggregates were recorded, and the morphology of the aggregates was measured by fluorescence microscope. Narrow and intense J-band at 580 nm in the absorption spectrum is the evidence that J-aggregates of PIC were produced. Small stokes shift in the fluorescence spectrum is the peculiarity of J-aggregate on the base. Typical fluorescence micrograph shows that microcrystalline J-aggregates （2 - 4 μm） precipitated separately on mica. The results indicate that J-aggregates of PIC were produced at a mica/air interface. The formation mechanism of J-aggregates may result from the epitaxial interaction between the positively charged N atoms of PIC molecules and the negative holes left by the dissociating K ^＋ ions of mica.