Facile synthesis of transparent and fluorescent epoxy-CdSe-CdS-ZnS core-multi shell polymer nanocomposites

A facile and environmentally benign approach for the synthesis of highly transparent and fluorescent CdSe-CdS-ZnS core-multi-shell polymer nanocomposites is presented. The CdSe-CdS-ZnS core-multi-shell quantum dots (QDs) were prepared via a continual precursor injection and phosphine free method in paraffin liquid and oleic acid without a protective atmosphere. The as-prepared core-multi-shell QDs were dispersed directly in an epoxy polymer matrix via a melt mixing technique. The QDs showed better dispersibility and good optical properties in the epoxy matrix. The transmission electron microscopy (TEM) images showed that the as-synthesized QDs are small, spherical and are well dispersed inside the polymer matrix without any change in morphology. It was found that the nanocomposite filled with yellow-emitting QDs had more transparency compared to the neat epoxy. The luminescence of the neat polymer shifted from the blue region to the yellow region in the nanocomposite. The fluorescent lifetime analysis of the as-prepared core-multi shell and the polymer nanocomposite showed a decrease compared to the core while the tensile measurements showed an increase in the tensile properties of the nanocomposite in comparison with the neat polymer.