We have synthesized hybrid particles by embedding CdSe/ZnS quantum dots (QDs) into wrinkled silica nanoparticles. We found that increasing the QD loading decreased the quantum yield (QY) of the wrinkled silica-QD hybrid particles. Compared to the previously-reported silica-QD hybrid particles, the wrinkled silica-QD hybrid particles exhibited higher QY, because the QD surfaces were not chemically modified during the hybridization process. The hybrid particles and free QDs were then used to prepare QD/photoresist nanocomposites. Since photoresist resin contains non-solvent for QDs, nanocomposites containing free QDs showed noteworthy aggregation even at 1.5 wt%, which resulted in deteriorated efficiency and stability. However, we were able to fabricate QD/photoresist nanocomposites successfully using hybrid particles up to 30 wt%, as the wrinkled silica nanoparticles helped in the dispersion of the QDs. By varying the concentration of hybrid particles in the nanocomposites, we found that the hybrid particles at 20 wt% exhibited the highest quantum efficiency. Testing of wrinkled silica/photoresist nanocomposites (without QDs), fabricated with different concentrations of the wrinkled silica nanoparticles, revealed that the highest efficiency at 20 wt% hybrid particles was the result of enhanced scattering by the wrinkled silica nanoparticles. Finally, simple devices in which hybrid particles were placed on blue µ-LEDs were fabricated, and their luminescence properties were analyzed.
Bibliographical noteFunding Information:
This work was supported by a National Research Foundation of Korea (NRF) (grant nos. NRF-2018R1A5A1024127 , 2017R1A2B4007534 , and 2016R1A2B4008869 ) funded by the Korean government, and the Ministry of Trade, Industry & Energy (grant no. 10079347 ) through the Development of Materials and Core-technology for Future Display support program. Authors would like to express thanks to the Korea Photonics Technology Institute for providing µ-LED.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering