White Organic Light‐Emitting Diodes with Evenly Separated Red, Green, and Blue Colors for Efficiency/Color‐Rendition Trade‐Off Optimization

• DOI: 10.1002/adfm.201100895
• Publication Date: 2011-08-03T20:41:55Z
• Authors: Shuming Chen; Guiping Tan; Wai‐Yeung Wong; Hoi‐Sing Kwok
• Keywords: Color rendering index; Quantum Efficiency; Luminous efficacy; Monochromatic color; High color

Abstract A novel yellowish‐green triplet emitter, bis(5‐(trifluoromethyl)‐2‐ p ‐tolylpyridine) (acetylacetonate)iridium(III) (1), was conveniently synthesized and used in the fabrication of both monochromatic white organic light‐emitting diodes (WOLEDs). At optimal doping concentration, devices based on 1 exhibit a high efficiency 63 cd −1 (16.3% 36.6 lm W ) at luminance 100 m −2 . By combining with phosphorescent sky‐blue bis(3,5‐difluoro‐2‐(2‐pyridyl)phenyl)‐(2‐carboxypyridyl)iridium(III) (FIrPic), red bis(2‐benzo[ b ]thiophen‐2‐yl‐pyridine)(acetylacetonate)iridium(III) (Ir(btp) 2 (acac)), resulting electrophosphorescent WOLEDs show three evenly separated main peaks give 34.2 (13.2% 18.5 When is mixed deep‐blue fluorescent 4,4′‐bis(9‐ethyl‐3‐carbazovinylene)‐1,1′‐biphenyl (BCzVBi), Ir(btp) (acac), hybrid demonstrate color‐rendering index 91.2 CIE coordinates (0.32, 0.34). The efficient highly color‐pure red, green, blue outperform those state‐of‐the‐art fac ‐tris(2‐phenylpyridine)iridium(III) (Ir(ppy) 3 ), are ideal candidates for display lighting applications.