Molecular Engineering of a Rigid Tetradentate Pt(II) Emitter for High‐Performance OLEDs Realizing the BT.2020 Blue Gamut
Abstract
Abstract Organic light‐emitting diodes (OLEDs) hold great promise for next‐generation ultra‐high‐resolution 4 K/8 K display technologies. However, the development of high‐efficiency deep‐blue OLEDs based on tetradentate Pt(II) emitters that simultaneously meet the BT.2020 blue color gamut and low efficiency roll‐off remains a formidable challenge. In this study, we designed a rigid, narrow‐spectrum, deep‐blue phosphorescent Pt(II) emitter, PtCK1, by strategic regulation of excited‐state properties and incorporation of bulky three‐dimensional steric geometry. PtCK1 exhibits excellent photophysical properties, including a small full width at half maximum (FWHM) of 15.6 nm and a high photoluminescence quantum yield of 97%. As a result, PtCK1‐bottom‐emitting OLED achieves deep‐blue emission with a peak at 460 nm, an FWHM of 21 nm, and a maximum external quantum efficiency of 25.3%. Even at luminance levels of 5000 cd m −2 , the EQEs remain as high as 19.3%. Impressively, top‐emitting phosphorescent OLED achieves improved color purity, with an ultranarrow spectrum (FWHM = 14 nm), Commission Internationale de l'Éclairage (CIE) coordinates of (0.139, 0.046), fully satisfying the BT.2020 blue standard, and especially a record‐high maximum blue index (BI) of 397 cd A −1 CIE y −1 with CIE y < 0.05. This study provides a valuable strategy for developing high‐performance tetradentate Pt(II) emitters that meet the BT.2020 blue gamut.
Article Details
Authors (8)
Kewei Xu
Chengyao Zhang
Liping Yang
International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Department of Chemistry, College of Sciences
Feng Zhan
Weiwei Lou
Center for Phosphorescent Material Research State Key Laboratory of Green Chemical Synthesis and Conversion College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310014 P.R. China
Yun‐Fang Yang
Center for Phosphorescent Material Research State Key Laboratory of Green Chemical Synthesis and Conversion College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310014 P.R. China
Yuanbin She
Center for Phosphorescent Material Research State Key Laboratory of Green Chemical Synthesis and Conversion College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310014 P.R. China
Guijie Li
Department of Chemistry, University of California 2 , Davis, California 95616,