High‐color‐quality phosphorescent white organic light‐emitting diodes utilizing broad‐spectrum yellow emitters

Abstract Lighting sources resembling sunlight with less blue hazards are desirable in today's world. Herein, we present a strategy for constructing low‐energy white organic light‐emitting diodes (WOLEDs) consisting of blue and yellow emissive layers (EMLs). Two new Pt (II) complexes, PtA‐Y and PtB‐Y, were developed as super broad‐spectrum yellow emitters featuring dual‐emission bands. The yellow OLEDs incorporating the broad‐spectrum emitter were adjusted to fully cover the region from green to deep red with the full‐width of half maximums over 150 nm. By adding the complementary blue EML, WOLEDs achieved a high color‐rendering index of 95 at a correlated color temperature of 3767 K with less blue but more deep red emission, minimal color shift with the Commission Internationale de l’Elcairage coordinates shift CIE ( Δx , Δy ) of (0.008, 0.001) in the luminance range of 178∼1168 cd m −2 , and long device operational half lifetimes over a hundred hours at 1000 cd m −2 . The strategy of constituting high‐color‐quality WOLEDs demonstrated here may assist the development of healthy lighting sources, feasibly having healing functions of flexible profile in the future.