Fabrication of highly transparent and luminescent quantum dot/polymer nanocomposite for light emitting diode using amphiphilic polymer-modified quantum dots

Herein we present the fabrication of a highly transparent and luminescent quantum dot (QD)/polymer nanocomposite for application in optoelectronic devices. First, we encapsulated CdSe@ZnS/ZnS core/shell QDs with an amphiphilic polymer, i.e., poly(styrene-co-maleic anhydride) (PSMA). By encapsulating QDs with PSMA instead of ligand exchange, the photoluminescence intensity of the QDs could be preserved even after surface modification. Next, the PSMA-modified QDs were used as crosslinkers for the aminopropyl-terminated polydimethylsiloxane (PDMS) resin in a ring-opening reaction between the maleic anhydride of the QDs and the diamines of the PDMS, producing polymer networks at a low curing temperature. This method afforded a nanocomposite with uniform dispersion of QDs even at high QD concentrations (~30 wt%) and superior optical properties compared to a nanocomposite prepared from unmodified QDs and commercial resin. Owing to these enhanced properties, the nanocomposite was used to fabricate a light emitting diode (LED) device, and the luminous efficacy was found to be highest at 1 wt%.