D3 陳宇輝君の「高効率・長寿命有機ELのための Ag と相互作用するジピリミジルピリジン誘導体多機能性電子輸送材料」の論文が日本化学会の Bull. Chem. Soc. JPN (IF: 3.8) に受理されました！陳、おめでとう！
本研究は、JST SICORP (JPMJSC2007)、JSPS 科研費（基盤研究B 23H02032, 23K26725）の助成を受けたものです。
Title: A Multifunctional Dipyrimidylpyridine Electron-Transporter Combined with Ag for Robust and Efficient Organic Light-Emitting Diodes
By Yuhui Chen, Takeshi Sano*, Naoki Meguro, Taisei Kotaka, Junji Kido, Hisahiro Sasabe*, Bull. Chem. Soc. JPN accepted.
Abstract: The development of state-of-the-art organic light-emitting diode (OLED) displays still faces two unavoidable challenges: lowering power consumption and achieving long operational stability. These difficulties largely originate from the complex multilayer OLED architecture, where several organic/organic and organic/inorganic heterointerfaces critically influence charge injection, carrier balance, and long-term stability. To address these interface-related issues, we designed a multifunctional electron-transport material, DPmPy-DBF1, that enables efficient electron injection when combined with silver (Ag). DPmPy-DBF1 integrates a dipyrimidylpyridine (DPmPy) unit, capable of strong Ag coordination, with a thermally robust dibenzofuran (DBF) unit through a meta-phenylene linker. This design suppresses excessive conjugation, increases conformational diversity, and produces an amorphous thin film with a high triplet energy of 2.9 eV. The material exhibits excellent thermal stability, including a glass-transition temperature of 127 °C, and favorable energy alignment that mitigates electron accumulation at organic/organic interfaces. When doped with Ag, DPmPy-DBF1 demonstrates superior electron-injection ability, as confirmed by UPS analysis and electron-only devices. A green phosphorescent OLED using DPmPy-DBF1 as a hole-blocking, electron-transport, and electron-injection layer achieves a low turn-on voltage of 2.18 V, a maximum EQE of 20.7%, and an extended operational lifetime (LT70 = 6389 h at 1000 cd m⁻²). These results highlight DPmPy-DBF1 as a promising multifunctional material for next-generation OLEDs.
