博士修了生 鎌田嵩弘君 (Dr. Takahiro Kamata) と笹部久宏准教授のTADF型有機ELの高効率・低電圧・長寿命を同時に実現する多機能性ホール輸送材料群に関する「Simultaneous Realization of High-Efficiency, Low-Drive Voltage, and Long Lifetime TADF OLEDs by Multifunctional Hole-Transporters」と題する論文が RSC の J. Mater. Chem. C (IF: 6.641) に受理されました！鎌田、望、おめでとう！
本論文は山形大学の横山研究室との共同研究論文です。横山先生、鮏川君、ありがとうございました。
Title: Simultaneous Realization of High-Efficiency, Low-Drive Voltage, and Long Lifetime TADF OLEDs by Multifunctional Hole-Transporters
By T. Kamata, H. Sasabe,* N. Ito, Y. Sukegawa, A. Arai, T. Chiba, D. Yokoyama, J. Kido*, J. Mater. Chem. C 2019, accepted.
Abstract: Although organic light emitting devices (OLEDs) based on thermally activated delayed fluorescence (TADF) have already realized impressively high external quantum efficiency (EQE) of over 35%, their operation lifetime should still be improved for practical applications. In this study, we developed a molecular design for high triplet energy (ET = 2.7 eV) multifunctional hole-transport layers (HTLs) based on a hexaphenylbenzene skeleton to realize record-breaking efficient and stable TADF OLEDs. By using a dibenzofuran-end-capped HTL named 4DBFHPB, we could successfully develop a highly efficient, low-drive voltage, and stable green TADF OLED exhibiting EQE of 19.2% and operation lifetime at 50% (LT50) of ~24,000 h at an initial luminance of 1000 cd m−2. The drive voltage at 1000 cd m−2 was recorded to be 4.07 V. We also developed a sky-blue TADF OLED exhibiting hext of 21.5% and LT50 of ~1700 h at an initial luminance of 500 cd m−2. The developed designs demonstrate record-breaking performances among the existing TADF OLEDs.
