Abstract
This investigation is concerned with a supersensitization phen~menon for CdS sensitized by the combinations of two dyes. As experimental results, the photoconductivity could be supersensitized by dye combinations. But the essential photoconductive sensitivity has decreased its value compared with the case of dye-sensitized CdS which adsorbed single dye on CdS surface.
We conclude that the desensitization of photoconductive sensitivity can be caused by the increase of shallow trapping levels and the darkcurrent owing to injecting electrons thermally from the number of shallow trap depths to conduction band of CdS.