Photoluminescence investigation of MPA–ZnS QDs interaction with selenite ion (original) (raw)

2017, Journal of the Iranian Chemical Society

quantum yields, superb photostability and long fluorescence lifetimes. Additionally, modification of the QDs with suitable functional groups or ligands has a profound effect on the photoluminescence response of desired target [1, 2]. Accordingly, owing to the novel and incomparable properties than most organic fluorescent dyes, utilization of these nanomaterials is very interesting for photoluminescence investigation of the interactions and development of the optical sensors in relation to the inorganic ions, drugs, toxicant, organic dyes, explosive compounds and biomolecular [1, 3]. Consequently, it has been widespread interest in numerous studies, published in recent years. The optical, physical and chemical properties of QDs, including the luminescence yield, activity, solubility in diverse solvents, photochemical stability and interaction with different targets are influenced by their surface chemistry. Numerous capping or stabilizing agents such as thiols, amines, carboxylic acids and phosphonates used for adaptation of surface chemistry and result in passivation of QDs surface traps from the perspective of the electronic and chemical features and could induce the enhancement of QDs photoluminescence intensity [4, 5]. This passivation of surface traps was generated either directly during synthesis or by post-synthetic modification [4, 6]. Toxic heavy-metal elements such as Cd, Hg and Pb are presenting as an inseparable part of most QDs. ZnS QD, one of the first commonly used semiconductors and a free heavy-metal system that is non-toxic in a wide range of concentrations, shows photoluminescence in the blue range and excellent chemical, optical and photocatalytic properties. Accordingly, this biocompatible QD with wide band gap energy offered notable features for manifold applications such as using for the removal of dyes and hazardous materials and designing the laser, photodetector and sensor [7-11].