【作者】 曹宁；

【导师】 杨少鹏；

【作者基本信息】 河北大学 ， 光学， 2005， 硕士

【摘要】 本研究利用皮秒时间分辨荧光发射光谱检测手段,研究了不同浓度的几种菁染料吸附在T型和立方体型两种晶型溴化银感光乳剂颗粒表面形成J-聚集体后进行的染料光谱增感微观机理,详细分析了不同增感条件对光谱增感体系电子转移过程的影响,进而得到其对增感效率的影响关系。 通过时间分辨荧光发射光谱检测,发现菁染料1798、55026和8701吸附在立方体型和T型AgBr乳剂颗粒表面形成的J-聚集体荧光衰减曲线均用双指数函数得到很好的拟合结果,存在一快一慢两个衰减成分,快衰减成分占拟合较大比例,研究认为其源于与荧光衰减相竞争的从激发态染料聚集体到AgBr导带的电子转移。染料B1251吸附在立方体和T型颗粒表面形成的J-聚集体荧光衰减分别用双指数和三指数函数很好的拟合,都存在快衰减成分。研究发现了染料8701、B1251和浓度较低的染料55026对立方体AgBr乳剂颗粒增感效率要高于T颗粒乳剂的增感效率;染料1798和浓度较高的染料55026对T颗粒AgBr乳剂增感效率高于立方体颗粒的论据。因此本研究为感光乳剂染料增感体系的开发与应用提供了理论基础。更多还原

【Abstract】 On the basis of picosecond time-resolved fluorescence spectroscopy, we studied the spectral sensitization micromechanism of four cyanine dyes J-aggregate absorbed on the tabular and cubic AgBr microcrystals with different concentration. We detailed analyzed the dependence of the electron transfer and the efficiency of spectral sensitization in the dye sensitized system on different conditions.With the time-resolved fluorescence spectroscopy, we found that the fluorescence decay curves of cyanine dyes J-aggregate of dye1798, dye 55026 and dye 8701 absorbed on the tabular and cubic AgBr microcrystals are fitted by a sum of the double exponential functions, and the fitting curves are consisted of a fast and a slow components. Because of the large amplitudes of the fast decay, this fast decay should be mainly attributable to the electron transfer from J-aggregate of dye to conduction band of AgBr. The fluorescence decay curves of J-aggregate of dye B1251 absorbed on two types of AgBr microcrystals are fitted by a sum of two and three exponential functions, respectively. We found that there is a fast component in all the fitted curves. In this paper, we found the sensitized efficiency of dye 8701, dye B1251 and dye 55026 of low concentration for cubic AgBr microcrystals is higher than that of the tabular. In contrast, the sensitized efficiency of dye 1798 and dye 55026 of high concentration for cubic is lower than that of the tabular. So the research provides the development and applications of the dye-sensitized system of photosensitive emulsion with theories foundation.更多还原