The doping of [IrCl 6 ]4-in cubic AgCl emulsion

Abstract

Dopants can be substitutionally incorporated into AgX crystals and influence the photoelectron action and the latent image formation by introducing appropriate electron traps. The dopant [IrCl 6 ] 4- was introduced in either the core, the subsurface shell or the outer shell of cubic AgCl microcrystals and its concentration was varied from 2.60 X 10 -7 mol/molAg up to 2.61 X 10 -5 mol/molAg. The emulsion sample exposed to a YAG super short pulse laser (355nm, 35ps) were measured by microwave absorption and dielectric-spectrum technique. The experimental results show the photoelectron decay time at room temperature decreases with the doping concentration increasing for any given doping position especially as the doping near the core. Results also show the photoelectron decay time at room temperature increases when the doping position is closer to the surface especially for higher doping concentration at 2.61 X 10 -5 mol/molAg. This can be explained that [IrCl 6 ] 4- can act as both shallow electron trap and deep electron trap with doping condition varying. When the doping level is lower and doping position is closer to the surface, the sensitivity of AgCl emulsion is higher. The knowledge obtained from this study may be useful for practical microcrystal design making use of dopants.