The Study of Decay Characteristics of Photoelectrons in Cubic AgBr Sensitized by PbS Nanoparticales

doi:10.7517/j.issn.1674-0475.2006.01.9

Abstract

Abstract: PbS nanoparticales as a sensitizer is added to the 0.8 μm cubic silver bromide emulsion for the chemical sensitization. Under illuminated by pulse laser, the decay characteristics of free photo-electrons and shallow-trapped electrons in the cubic silver bromide emulsion sensitized by PbS nanoparticales with the continuous increase of sensitization time are obtained by using the microwave absorption and dielectric spectrum measure technique. The influence of electron traps in silver bromide microcrystal, on the behavior of the photoelectron’ s movement is discussed. The relationship between the effects of electron traps and sensitization time is analyzed. By the contrast of the decay characteristics between the unsensitized sample and the sensitized samples, the optimum sensitizing-time on this experiment condition is 60 min.

Key words: microwave absorption, PbS nanoparticales, decay time, electron trap

CLC Number:

TQ57

YANG Shao-peng, ZHENG Hong-fang, FU Guang-sheng, LI Xiaowei, XU Chun-hua, LI Jin-pei. The Study of Decay Characteristics of Photoelectrons in Cubic AgBr Sensitized by PbS Nanoparticales[J]. Imaging Science and Photochemistry, 2006, 24(1): 9-16.

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