Hyunkwon Shin

Robust, processable, and bright quantum dot/organosilicate hybrid films with uniform QD distribution based on thiol-containing organosilicate ligands

Robust, processable, and bright quantum dot/organosilicate (QD/OS) hybrid films with uniform QD distribution are successfully demonstrated by grafting thiol-containing polymeric organosilicate (OS) ligands to the surface of QDs. It is found that the surface modified QDs show almost the same optical properties (i.e., in terms of emission PL spectra and quantum yields (QYs)) as those of pristine QDs initially covered with oleic acids. The QD/OS hybrid films based on the surface modified QDs show the uniform distribution of QDs within the films with all the beneficial properties such as high QY, improved environmental resistance against hydrochloric acid, and excellent optical transparency in the visible range. In addition, red, green, blue, and white QD/OS hybrid films with high color purity and a down-conversion film, based on a mixture of red and green QDs, placed on top of a blue LED chip showing white emission were also successfully demonstrated with the QD/OS hybrids. We further demonstrate that cylinder-patterned QD/OS hybrid films are possible simply by applying unconventional imprint lithography. The QD/OS hybrid films with uniform distribution of QDs within the films could thus be applied as practical platforms, which have easy processability, high QY, and environmental stability, for optical devices based on functional nanocrystals.