The Study Of Photoelectron Characteristic Of Spectral Sensitized Cubic Silver Chloride Emulsion

The study of effect of dye adsorption on silver halide is helpful for the spectral sensitization. The action of dye adsorption on cubic silver chloride is studied by spectral technology, microwave absorption and dielectric spectrum detection technology and theoretically relation of photoelectron decay microcosmic kinetics in this work.At first, the effect of dye adsorption on the structure of silver halide microcrystals is studied. The light of 355nm wavelength which belongs to the intrinsic absorption area of silver halide is selected to expose the spectral sensitized cubic silver chloride emulsion. The photoelectron decay curves are measured by microwave absorption and dielectric spectrum detection technology, and the influence of sensitization condition on the photoelectron decay is analyzed. It is found that with the sensitization concentration increasing and the sensitization time prolonging, photoelectron decay of sensitized emulsion become firstly slower, then faster and last slower again. Combining with photoelectron decay kinetics, the experimental results are explained from the aspect the theory. The result shows that when the dye adsorbed in silver chloride is little, it makes the deep electron traps in microcrystals decrease by decorating the energy level of microcrystals surface; when the dye adsorbed in silver chloride is much, it makes the deep electron traps in microcrystals increase by increasing the Agi+ in microcrystals; when the dye adsorbed in silver chloride reaches a certain extent, the later function has little change and the former function increasing again, so the deep electron traps in microcrystals decrease again. And the conclusion that the surface not the inside of silver halide is mainly decorated by the dye adsorption is obtained from the theoretical analysis. Then the influence of dye adsorption on the spectral sensitization is studied. Based on the analysis of absorption characteristic of sensitizing dye, the light of 532nm wavelength which belongs to the absorption area of dye is selected to expose the spectral sensitized emulsion. It is found that the deep electron traps in microcrystals also increase when the dye adsorbed in silver chloride is little, and on the whole the photoelectron decay in 532nm wavelength is faster than that in 355nm, which is induced by the different intensity of photoelectron and area effect of microcrystals surface. At last, the photoelectron kinetics of desensitization is studied. Based on the analysis of absorption characteristic of desensitizing dye the free photoelectron decay curves of desensitized silver chloride emulsion exposed by 532nm are measured by microwave absorption and dielectric spectrum detection technology. From the analysis of the influence of desensitizing dye on photoelectron intensity and decay, it is found that the desensitizing dye not only influence the photoelectron intensity by absorbing light competitively with sensitizing dye, but also accelerate the photoelectron decay of sensitized emulsion by trapping the photoelectron in the spectral sensitized area. The results of this work are valuable for the analysis of crystal structure, and can instruct the dye to be used in more fields such as spectral sensitization of photoelectric materials.