A novel molecular design featuring the conversion of inefficient TADF emitters into efficient TADF emitters for deep-blue organic light emitting diodes

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2021-07, Vol.416, p.129097, Article 129097
• Main Authors: Konidena, Rajendra Kumar, Lim, Junseop, Lee, Jun Yeob
• Format: Article
• Language: English
• Subjects: Blue; Efficiency; OLED; TADF
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2021.129097

[Display omitted] •Transformation of inefficient thermally activated delayed fluorescent emitters into efficient emitter.•Coupling of the non-TADF type chromophore through a phenyl linker in a sterically hindered way.•Maximum external quantum efficiency of 22% with a y color coordinate of 0.15. In this report, we unveiled a new molecular design featuring the transformation of inefficient thermally activated delayed fluorescence (TADF) emitters into the efficient TADF emitters by combing them with non-TADF type chromophore units to develop deep-blue TADF emitters for organic light-emitting diodes. The inefficient TADF emitter and non-TADF chromophore were connected directly through a phenyl linker in a sterically hindered configuration by selectively interlocking two donors in the backbone structure. The new TADF emitter demonstrated excellent device performances with maximum external quantum efficiency up to 22% and y color coordinate of 0.15. Based on these results, we believe that the proposed new design strategy is effective with regard to the conversion of inefficient deep-blue TADF emitters to efficient deep-blue TADF emitters and can be diversely applied for the development of efficient TADF emitters.