Violet-Blue Emitters Featuring Aggregation-Enhanced Emission Characteristics for Nondoped OLEDs with CIEy Smaller than 0.046

High
emission efficiency and finite molecular conjugation in the
aggregate state are two desirable features in violet-blue emitters.
Aggregation-induced emission luminogens (AIEgens) have emerged as
promising luminescent materials that offer these features. Herein,
we report the design and synthesis of a group of violet-blue tetraphenylbenzene-based
AIEgens with photoluminescence quantum yields over 98% in their film
states. When utilizing these AIEgens as nondoped emitting layers,
the fabricated organic light-emitting diode exhibits a maximum external
quantum efficiency of 4.34% with Commission Internationale de L’Eclairage
(CIE) coordinates of (0.159, 0.035), which is amenable to the next-generation
ultrahigh-definition television (UHDTV) display standard.