Photoluminescence quenching of CdTe/CdS core-shell quantum dots in aqueous solution by ZnO nanocrystals

► PL quenching of CdTe/CdS core-shell QDs was observed in the presence of ZnO nanocrystals. ► The PL quenching resulted in a decrease in PL lifetime and a small red shift of the PL band of CdTe/CdS core-shell QDs. ► CdTe(1.5)/CdS core-shell QDs exhibited higher efficiency of PL quenching than the CdTe(3.0)/CdS core-shell QDs. ► Electron transfer processes from CdTe/CdS core-shell QDs to ZnO nanocrystals were explained well by type II and type I QD models.