Brightness-enhanced, highly stable quantum dot light-emitting devices using butylated hydroxytoluene

Quantum dot (QD) light-emitting devices (LEDs) have recently attracted significant interest owing to their high luminance, easily adjustable color and narrow emission bandwidth. Although their luminance and efficiency have been improved, their lifetime is limited by the low chemical stability and photostability when exposed to air and water. In this study, we report on an easy method to improve QD LEDs (QLEDs) resistance to oxidation by dissolving butylated hydroxytoluene (BHT) in a CdSe/ZnS QD solution. The dissolved BHT improves stability and life expectancy because it is oxidized instead of the QDs. QLEDs fabricated using BHT-treated CdSe/ZnS QDs showed an improved luminance of 20660 cd/m² and a current efficiency of 3.16 cd/A. Moreover, the lifetime of the QLEDs with BHT-treated QDs was markedly improved over the untreated QLEDs because of the protection afforded by BHT.