Despite of useful applications of Ag, it is hazardous to health and environment and hence early detection is required. Crystal defects influencing optical property is less likely utilized for Ag detection using prevalent UV-Vis technique. Quantum dots (QDs) ZnS prepared by soft chemical route are exploited for the detection of Ag⁺ in aqueous solution for nM to mM concentrations. UV-Vis and photoluminescence (PL) measurements reveal quantum confinement effect and presence of defects in ZnS nanoparticles (NPs). Controlled synthesis of ZnS NPs allows appearance of defects related peak at 400–550 nm in UV-Vis spectra. A plausible mechanism is presented and elucidated by XRD and PL studies for chemical interaction between ZnS with Ag⁺. The interaction affects prominently the defects related absorption of ZnS NPs and allows single step Ag⁺ detection in aqueous medium. This absorption method is extended to other ions (Na⁺, K⁺, Mg⁺, Ca⁺, Ba⁺) including ‘S’ prone heavy and toxic ions like Pb, Hg, and Cd. Among them, Ag⁺ shows the best response with ZnS NPs. This demonstration using a portable and cost effective technique with no organic component opens up possibility for other inorganic materials.

尽管银有有用的用途，但它对健康和环境有害，因此需要及早发现。影响光学性质的晶体缺陷不太可能用于使用流行的UV-Vis技术进行Ag检测。通过软化学途径制备的量子点（QDs）ZnS被用于检测水溶液中nM到mM浓度的Ag ⁺。UV-Vis和光致发光（PL）测量揭示了量子约束效应和ZnS纳米颗粒（NPs）中缺陷的存在。ZnS NPs的受控合成允许在UV-Vis光谱中出现与缺陷相关的峰，其峰位于400-550 nm。通过XRD和PL研究提出并阐明了ZnS与Ag ⁺之间化学相互作用的合理机制。相互作用显着影响与ZnS NPs吸收有关的缺陷，并允许在水性介质中进行单步Ag ⁺检测。这种吸收方法扩展到其他离子（Na ⁺，K ⁺，Mg ⁺，Ca ⁺，Ba ⁺），包括“ S”型易重和有毒离子，例如Pb，Hg和Cd。其中，Ag ⁺表现出对ZnS NPs的最佳响应。使用便携式且具有成本效益的技术而没有有机成分的演示为其他无机材料开辟了可能性。