Donor-Acceptor Type Bifunctional Molecules with Hybridized Local and Charge-Transfer Excited State as Efficient Non-Doped Deep-Blue Emitters for Highly Efficient Fluorescent OLEDs

Herein, we synthesized two novel D–p–A fluorescent moleculesnamely PhAnsIn and PhAnoIn based on dimethyldihydroindenocarbazole–anthracene- phenanthroimidazole fornon-doped blue organic light-emitting diodes. The excited-stateproperties of the PhAnsIn and PhAnoIn investigated throughphotophysical experiments and density functional theory revealedthe HLCT excited-state characteristics. The neat films of PhAnsInand PhAnoIn exhibited photoluminescence quantum yields of80.6% and 56.5%, respectively. The non-doped devices based onPhAnsIn and PhAnoIn exhibited corresponding blue emissionswith electroluminescence peaks at 458 and 457 nm, a maximumEQE of 8.2% and 8.5% with CIE coordinates of (0.14,0.12) and(0.14,0.11), respectively.