Thermally Stimulated Luminescence of InP/ZnS Colloidal Quantum Dots

For the first time, spectrally resolved thermally stimulated luminescence in InP/ZnS core/shell colloidal quantum dots after exposure to UV radiation at 7 K were studied. Analysis of the measured emission spectra showed that the recombination of charge carriers localized under irradiation and released upon further stimulation occurs with the participation of defect centers based on dangling indium and phosphorus bonds. Using the initial rise method and the formalism of general-order kinetics, the kinetic features of possible thermally stimulated mechanisms were analyzed, and the energy characteristics of the corresponding capture centers were estimated. Active traps in the studied nanocrystals were found to be characterized by close activation energy values in the range of 25–29 meV.