Highly efficient deep-blue fluorescence OLEDs with excellent charge balance based on phenanthro[9,10-d]oxazole-anthracene derivatives

Abstract

<p>Two blue fluorescent materials, m-PO-ABN and p-PO-ABN, are newly synthesized by controlling the conjugation length based on different linkages of the meta or para position between the phenanthro[9,10-d]oxazole (PO) moiety...</p>

Ornamenting of Blue Thermally Activated Delayed Fluorescence Emitters by Anchor Groups for the Minimization of Solid-State Solvation and Conformation Disorder Corollaries in Non-Doped and Doped Organic Light-Emitting Diodes

“…Investigation of charge-transporting properties of potential functional materials for OLED applications is vitally important because holes and electrons have to recombine within light-emitting layers of OLEDs. 50 In the ideal case, non-doped light-emitting layers of OLEDs are characterized by bipolar/ambipolar charge-transporting properties with well-balanced hole and electron mobilities. Otherwise, the appropriate host has to be selected.…”

Rhodium-Catalyzed Aerobic Decomposition of 1,3-Diaryl-2-diazo-1,3-diketones: Mechanistic Investigation and Application to the Synthesis of Benzils

“…We anticipated that the protocol could also be used for the synthesis of 9,10-phenanthrenequinone ( 3t ) and benzocyclobutene-1,2-dione ( 3u ), the compounds that have found wide applications in organic synthesis and many other areas. , To this end, diazo precursors 1t and 1u were first prepared from either ethyl 2-bromobenzoate in a three-step sequence ( 7 → 8 → 1t ), or commercially available 1,3-indanedione by a single diazo transfer reaction (Scheme ). In comparison to the 1,3-diaryl-2-diazo-1,3-diketone system, the decomposition of 1t / u to 3t / u turned out to be more formidable presumably owing to unfavorable strain and rigidity of the ketene intermediates.…”

Highly Efficient Multifunctional Luminogens for Near UV/Deep Blue (CIEy ∼0.02) and Hybrid White OLEDs (CIE ∼0.33, 0.37) with Superior Color Stability

“…Generally, the charge transfer in the simple donor–acceptor structure can realize the unwanted redshifted emission, which ultimately does not favor obtaining violet/deep blue emission with color coordinate CIE y value <0.05. To overcome these encountered problems, the structural molecular design (beyond the conventional way of connecting donor–acceptor moieties in a single fluorophore structure) plays a crucial role that it can separate the charge injection group, selection of electron-donating/withdrawing moiety with proper inductive strength, suppression of π-conjugation length, and intramolecular charge transfer (ICT) effect to minimize their interactions …”

“…To overcome these encountered problems, the structural molecular design (beyond the conventional way of connecting donor−acceptor moieties in a single fluorophore structure) plays a crucial role that it can separate the charge injection group, selection of electron-donating/withdrawing moiety with proper inductive strength, suppression of πconjugation length, and intramolecular charge transfer (ICT) effect to minimize their interactions. 17 In comparison to prior generations of emitters (phosphorescent molecular complexes/thermally activated delayed fluorescence (TADF) based emitters), extensive attempts have been made to date to investigate the various NUV− blue fluorescent emitters. At present, very few reports are available based on violet−blue emitters with good efficiency.…”