The irradiation influence on the properties of silver sulfide (Ag$_{2}$S) colloidal nanoparticles

The aqueous solutions of different stability containing silver sulfide (Ag$_{2}$S) nanoparticles are studied. The stable, transparent, and turbid solutions have been subjected to daylight for 7 months, to ultraviolet and laser irradiation, as well as to an electron beam. Solar radiation is found to favor the Ag$_{2}$S reduction to Ag and/or the formation of Ag$_{2}$S/Ag hybrid nanoparticles in the solution. At a high amount of hybrid nanoparticles, the exciton–plasmon interaction causes asymmetry in the absorption spectra. The exposure of Ag$_{2}$S particles precipitated from the solution with the electron beam leads to the reversible growth of Ag threads. The possible exciton–plasmon interplay mechanisms in Ag$_{2}$S/Ag hybrid nanoparticles are considered. The physical mechanisms of the changing Ag$_{2}$S stoichiometry, the formation of metallic Ag and Ag$_{2}$S/Ag hybrid nanoparticles are the generation of hot carriers and the energy transfer (exciton–plasmon interaction) in a metal–semiconductor hybrid nanosystem are elucidated, as well.