Temperature behavior of the Optical Absorption and Photoluminescence Spectra of InP/ZnS Nanocrystals with a Stabilizing Polyvinylpyrrolidone-based Coating

: The present paper deals with the results of a research work on the optical properties of colloidal InP/ZnS nanocrystals stabilized with a heterobifunctional polyvinylpyrrolidone polymer. We have analyzed the absorption and photoluminescence spectra of the samples as solutions with various concentrations and deposited films, as well as the patterns of their temperature changes in the range of 6.5–296 K. An inhomogeneous broadening of exciton optical bands has been observed to be related to a wide distribution of nanocrystals in size. A temperature shift of the exciton absorption and emission maxima has been found to be due to the interaction with acoustic phonons. It has been shown that the quenching of defect-related luminescence is carried out through local energy levels of dangling bonds of phosphorus atoms involved at the core-shell interface, and the temperature stability of exciton emission is determined by the thickness of the ZnS shell.