Back to Search
Start Over
Developing deep blue (CIEy < 0.08) and pure blue (CIEy < 0.11) OLEDs via molecular engineering of carbazole moiety.
- Source :
-
New Journal of Chemistry . 9/28/2021, Vol. 45 Issue 36, p16732-16739. 8p. - Publication Year :
- 2021
-
Abstract
- Recently, numerous efforts have been devoted to sky blue or greenish blue organic light-emitting diodes (OLEDs), nevertheless, the deep blue and pure blue OLEDs still remain a formidable challenge. Herein, a series of deep blue and pure blue donor–acceptor–donor (D–A–D) type emitters, namely Cz-DMTD, PhCz-DMTD and TMCz-DMTD, were constructed. For PhCz-DMTD which exhibited no delayed fluorescence component, the extended delocalization of donors and the enhancement of oscillator strength were both observed through theoretical calculation. For methyl-engineered TMCz-DMTD, the degenerate charge transfer singlet excited (1CT) and triplet excited (3CT) states and localized triplet excited (3LE) state endowed a thermally activated delayed fluorescence (TADF) character. Moreover, PhCz-DMTD and TMCz-DMTD based OLEDs displayed emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.164, 0.077) and (0.157, 0.107) and with maximum external quantum efficiencies (EQEmax) of 4.6% and 8.7%, respectively. It is the first time that the electroluminescence wavelength of TMCz based OLEDs reached below 450 nm with a CIEy below 0.11. Molecular engineering of the carbazole moiety is expected to provide a valuable strategy for molecular design of more deep blue emitters. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 11440546
- Volume :
- 45
- Issue :
- 36
- Database :
- Academic Search Index
- Journal :
- New Journal of Chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 152553286
- Full Text :
- https://doi.org/10.1039/d1nj02492b