Synthesis and characterization of quantum dot–polymer composites

Abstract

In this study, we demonstrate a facile and simple synthesis of quantum dot (QD)–polymer composites. Highly fluorescent semiconducting CdSe/ZnS quantum dots were embedded in different commercially available polymers using one easy step. QD–polymer composite nanoparticles were also synthesized using template-assisted synthesis. In particular, we self-assembled lamellar micelles inside nanoporous alumina membranes which were used for the synthesis of mesoporous silica hollow nanotubes and solid nanorods. We observed that the addition of excess free octadecylamine (ODA) in the QD–silica solution resulted in gelation. The gelation time was found to be dependent on free ODA concentration. Similarly, the emission of QD–polymer composites was also found to be dependent on free ODA concentration. Highly purified QDs provided polymer composites that have a much lower emission compared to unpurified nanocomposites. This was attributed to passivation of the QD surfaces by amine, which reduced the surface defects and non-radiative pathways for excited QDs. Finally, highly fluorescent QD–polymer patterns were demonstrated on glass substrates which retained their emission in both polar and non-polar solvents.