Kim, Jung Kyu Bae, Sukang Yi, Yeonjin Park, Myung Jin Kim, Sang Jin Myoung, NoSoung Lee, Chang-Lyoul Hong, Byung Hee Park, Jong Hyeok 2024-01-20T07:00:37Z 2024-01-20T07:00:37Z 2021-09-05 2015-06-11 2045-2322 https://pubs.kist.re.kr/handle/201004/125331 Polymer light emitting diodes (PLEDs) using quantum dots (QDs) as emissive materials have received much attention as promising components for next-generation displays. Despite their outstanding properties, toxic and hazardous nature of QDs is a serious impediment to their use in future eco-friendly opto-electronic device applications. Owing to the desires to develop new types of nano-material without health and environmental effects but with strong opto-electrical properties similar to QDs, graphene quantum dots (GQDs) have attracted great interest as promising luminophores. However, the origin of electroluminescence from GQDs incorporated PLEDs is unclear. Herein, we synthesized graphene oxide quantum dots (GOQDs) using a modified hydrothermal deoxidization method and characterized the PLED performance using GOQDs blended poly(N-vinyl carbazole) (PVK) as emissive layer. Simple device structure was used to reveal the origin of EL by excluding the contribution of and contamination from other layers. The energy transfer and interaction between the PVK host and GOQDs guest were investigated using steady-state PL, time-correlated single photon counting (TCSPC) and density functional theory (DFT) calculations. Experiments revealed that white EL emission from the PLED originated from the hybridized GOQD-PVK complex emission with the contributions from the individual GOQDs and PVK emissions. English NATURE PUBLISHING GROUP ENERGY-TRANSFER BLUE NANOCRYSTALS OXIDE EFFICIENT Origin of White Electroluminescence in Graphene Quantum Dots Embedded Host/Guest Polymer Light Emitting Diodes Article 10.1038/srep11032 1 SCIENTIFIC REPORTS, v.5 SCIENTIFIC REPORTS 5 scie scopus 000356096900001 2-s2.0-84931262324 Multidisciplinary Sciences Science & Technology - Other Topics Article ENERGY-TRANSFER BLUE NANOCRYSTALS OXIDE EFFICIENT PLED Graphene quatum dots White luminescence