阴阳离子菁染料超快荧光动力学特性研究

采用飞秒荧光上转换技术,研究了阴阳离子菁染料及对应的阴离子和阳离子菁染料吸附在立方型和T型溴碘化银表面上形成J-聚集体的荧光衰减时间分辨特性,分析了几种菁染料增感体系的超快电子转移动力学过程及其对增感效率的影响.通过比较几种菁染料增感体系的荧光衰减特性,两种阴阳离子染料要明显快于阴离子染料、阳离子染料及二者的加合,说明阴阳离子染料聚集体到溴碘化银的电子注入速率较快,增感效果更好.对两种阴阳离子染料聚集体荧光衰减特性的比较,可以看出染料在T型颗粒溴碘化银上形成聚集体的荧光寿命更短,因而对T型颗粒的增感效果更好.染料Dye2的荧光衰减要快于染料Dye1,说明染料Dye2到溴碘化银的电子注入速率更快,增感效率更高.

Ultrafast Kinetics Characteristics of Fluorescence in Anionic-Cationic Cyanine Dyes

In this paper, the fluorescence decay property of J-aggregates of anionic-cationic cyanine dye, anion dye and cation dye adsorbed on cubic and tabular AgBrI grains is investigated using femtosecond fluorescence up-conversion technology. The kinetics of the ultrafast electron transfer and the spectral sensitization property in the dye sensitized system are analyzed in details. By comparing the fluorescence decay property of the sensitization system of several dyes, it is found the electron transfer velocities of J-aggregates of anionic-cationic dyes is larger than that of anion dye, cation dye and the mixed of anion dye and cation dye. The sensitized efficiency of anionic-cationic dyes for the tabular grains is higher than that for the cubic ones. Dye2 has higher sensitized efficiency than Dye1 for both kinds of AgBrI grains.