Solution-processed white organic light-emitting diodes with blue fluorescent and orange-red thermally activated delayed fluorescent dendritic luminogens

π‐Stacked Donor–Acceptor Dendrimers for Highly Efficient White Electroluminescence

“…As shown in Figure 5b,Device Dshows ablue emission band at % 470 nm coming from BD-Cy,and ayellow emission band at % 550 nm from YD-TF,leading to white electroluminescence with CIE coordinates of (0.32, 0.45) at 5V .Asthe voltage increases,the relative intensity of blue emission to yellow emission is increased, accompanied by CIE coordinates moving to (0.31, 0.42) at 8V .R emarkably,D evice Dr eveals al ow turn-on voltage (V on )o f2 .8 Vt ogether with high device efficiency with the maximum LE (LE max )of57.6 cd A À1 ,maximum EQE (EQE max )of20.6 %and maximum PE (PE max )of58.9 lm W À1 , representing the state-of-the-art efficiency for solution-processed all-TADF white OLEDs (Table S6). [33][34][35][36][37][38][39][40][41] ForDevice E with 20 wt %BD-Cy and 1wt% YD-TF as emitter, the CIE coordinates move to (0.32, 0.44) at the voltage of 8V . Meanwhile,t he device efficiencies decline to 55.2 cd A À1 , 19.2 %and 55.6 lm W À1 for LE max ,EQE max and PE max, respectively due to exciton quenching at high dopant concentration.…”

“…Solution-processed two-color white OLEDs based on blue and yellow p-stacked donor-acceptor dendrimers exhibit the maximum external quantum efficiencyof20.6 %and maximum power efficiency of 58.9 lm W À1 ,w hich are the state-of-the-art efficiencies for all-TADF white OLEDs by solution process (Table S6). [33][34][35][36][37][38][39][40][41]…”

A heterocycle fusing strategy for simple construction of efficient solution-processable pure-red thermally activated delayed fluorescence emitters

“…32 However, meeting all the above requirements always needs to integrate multiple functional groups together into one molecule, which is generally associated with multi-step metal-catalyzed coupling reactions. 25–28,35–37 This will inevitably increase the difficulty of purification and the synthetic cost of TADF molecules. Therefore, it is of vital importance to develop efficient and solution-processable red TADF emitters via a simple and green synthetic route.…”

Double-layer printed white organic light-emitting diodes based on multicomponent high-performance illuminants

“…Huang and his coworkers [22] reported single-emissive-layer WOLEDs by solution process and obtained a high efficiency of 18.9 cd A −1 at 280 cd m −2 using Firpic, Ir(ppy) 2 (acac), Ir(bt) 2 (acac), and Ir(piq) 2 (acac) as dopants. Dong and his coworkers [23], using 3ICz-Tr as a blue emitter and Tri-tNID as an orange-red emitter, obtained a maximum external quantum efficiency (EQE max ) of 8.32% without the need for a host material. Lee and colleagues [24] produced hybrid WOLEDs with a single EML, which consisted of 5-(4-(4,6-diphenyl-1,3,5triazin-2-yl)phenyl)-10,10-diphenyl-5,10-dihydrodibenzo[b,e] [1,4]azasiline (DTPDDA) as a blue thermally activated delayed fluorescence (TADF) emitter and Ir(MDQ) 2 (acac) as a phosphorescent red emitter, and obtained an EQE max of 6.16%.…”