P‐111: Tetradentate Ligand‐Based Novel Platinum(II) Complex and Its Outstanding Performance in Blue Phosphorescent Organic Light‐Emitting Diodes

Even though the remarkable growth of the organic light‐emitting diode (OLED) industry has occurred via continuous, extensive efforts toward the utilization of various organometallic luminophores as phosphorescent emitters, the development of blue phosphorescent emitters with improved efficiencies and high electrochemical stabilities is essential. To satisfy this, developing emitter featuring a narrow full width at half maximum (FWHM) is necessary. We herein designed and preparation of a novel tetradentate Pt(II) complex, Pt3, and its application as blue phosphorescent emitters in OLED devices. Pt3 exhibited intense blue emission in the solution and solid states with drastically narrow FWHM (21 nm). In addition, this complex displayed very high phosphorescent quantum efficiencies (96%) with a host material. Multilayer phosphorescent OLEDs containing Pt3 as an emitter with SiCzCz/SiTrzCz2 mixed host systems were fabricated. The devices exhibited outstanding performances, including high external quantum efficiencies (EQE = 18.6%), and operational lifetime (LT70 = 3947 h at 200 cd m ‐2 ). These results plainly suggest that tetradentate Pt(II) dopants are promising candidates as highly efficient, and stable blue phosphorescent emitters in OLEDs.