Phosphorescence quenching study of Cu(II)-ions-induced Mn-doped ZnS quantum dots revealed by intensity- and lifetime-resolved spectroscopy

Abstract Luminescence quenching of colloidal quantum dots (QDs) appeals many applications in optical sensors. Here, we have developed an intensity- and lifetime-resolved spectroscopy to reveal the phosphorescence quenching of Cu2+-induced Mn-doped ZnS QDs. Phosphorescence intensity and lifetime of QDs can be divided into three components corresponding to one by one. With increasing Cu2+ ions, the isolated Mn2+ emission is quenched by copper ions, but Mn-Mn pair and ZnS defect emissions exhibit the opposite trend. Phosphorescence quenching of QDs can be explained by the effective electron transfer from QDs to Cu2+.