城戸・笹部・千葉研究室D2 熊田健吾さんと笹部久宏准教授のフェニレン架橋環状多重共鳴型水色 TADF 材料群の論文が英国化学会 (Royal Society of Chemistry) の J. Mater. Chem. C (IF: 6.4) に受理されました。
本研究は、JSPS 科研費（基盤研究B, 20H02807）、NEDO 官民による若手研究者発掘支援事業 (21502128-0) の助成を受けたものです。
Title: Phenylene-Bridged Cyclic Multi-Resonance TADF Emitters for High-Efficiency and High-Color-Purity Sky-Blue OLEDs with EQE of 30%
By Kengo Kumada, Hisahiro Sasabe*, Misaki Matsuya, Naoto Yoshida, Keigo Hoshi, Takeru Nakamura, Haruki Nenma, Junji Kido*, J. Mater. Chem. C 2023, accepted.
Abstract: Although multi-resonance thermally activated delayed fluorescence (MR-TADF) emitters exhibit near-unity photoluminescence quantum yield (PLQY) and narrow-band emission, their aggregation-caused quenching (ACQ) and random molecular orientation in organic light-emitting devices (OLEDs) restrict the maximization of their full potential. In this study, we developed a series of novel phenylene-bridged MR-TADF emitters with varying numbers of carbazole units. These emitters exhibited sky-blue emission at approximately 480 nm with a near-unity PLQY, a small full width at half maximum of 26–31 nm, and horizontal molecular orientation of Q ~ 80%. The chemical modifications with a phenylene bridge and varied carbazole units reduced the ACQ behavior at high concentration ratios and greatly enhanced the Q values from 62% to 80%. The corresponding OLED exhibited an external quantum efficiency of approximately 30%.