Synthesis of CdS nanoparticles quantum dots capped by 2,2′-dithiodibenzoic acid and study of its interaction with some transition metal ions

► A new CdS quantum dot capped with 2,2′-dithiodibenzoic acid (DDBA) was prepared. ► The prepared QDs benefit from a favorable fluorescence. ► Interaction of some metal ions with the QDs was examined according to the Stern-Volmer equation. ► The determination of Ag(I) is feasible in the presence of many co-existence metal ions. ► The method benefits from high-speed and considerable simplicity for Ag(I) determination.