Silver sulfide nanoparticles with non-toxic citrate shell are synthesized by chemical bath deposition from aqueous mixtures of silver nitrate and sodium sulfide in the presence of sodium citrate used as a complexing and stabilizing agent. The prepared nanoparticles have Ag2S core with monoclinic crystal structure functionalized by a carbon-containing citrate shell. By varying the concentrations of reagents it was possible to prepare core-shell nanoparticles with pre-assigned size of Ag2S core from 10 and 50 nm and pre-assigned thickness from 1.5 to 10 nm of citrate shell. A probable mechanism of formation of carbon-containing citrate shell on Ag2S core has been proposed. (C) 2015 Elsevier B.V. All rights reserved.