Semiconductor photophysics. 5. Charge carrier trapping in ultrasmall silver iodide particles and kinetics of formation of silver atom clusters

Reactions of reducing species from acetonitrile media with silver iodide particles (∼25-angstrom diameter) have been investigated by pulse radiolysis techniques. Injection of electrons into these ultrasmall particles leads to transient bleaching of the adsorption of AgI at wavelengths close to the onset of absorption (∼400 nm) with the concomitant reduction of AgI to metallic silver. The reduction of Ag+ ions and formation of silver atoms and/or dimeric Ag2 molecules on three different size AgI particles (∼100, 35, and ∼25 angstrom) have also been examined by picosecond laser spectroscopy