Park Jongwook

9,10-Bis(3′,5′-diphenylphenyl)anthracene [MAM], 9-(3′,5′-diphenylphenyl)-10-(3‴,5‴-diphenylbiphenyl-4″-yl)anthracene [MAT], and 9,10-bis(3″,5″-diphenylbiphenyl-4′-yl)anthracene [TAT] were newly synthesized through boration and Suzuki aryl–aryl coupling reactions. We have demonstrated that the EL performance of blue-light emitters can be optimized and improved by varying the chemical structures of the side groups. In the thin film state, the three materials exhibit PLmax values in the range of 43

New blue fluorescent compounds containing tetra-substituted ethylene moieties have been designed and synthesized. These materials, 1,2-di(4′-tert-butylphenyl)-1,2-bis(4′-(anthracene-9-yl)phenyl)ethene [BPBAPE, 1A], 1,2-diphenyl-1,2-bis(4′-(anthracene-9-yl)phenyl)ethene [PBAPE, 1B], 9,10-bis(4-(1,2,2-tris(4-tert-butylphenyl)vinyl)phenyl)anthracene [BTBPPA, 2A], and 9,10-bis(4-(1,2,2-triphenylvinyl)phenyl)anthracene [BTPPA, 2B], were synthesized through Suzuki and McMurry reactions. By fabricating

We describe two novel blue emission materials based on a new type of dual core concept. 1-Phenyl-6-(10-phenyl-anthracen-9-yl)-pyrene (Ph-AP-Ph) and 1-[1,1′;3′,1′′]terphenyl-5′-yl-6-(10-[1,1′;3′,1′′]terphenyl-5′-yl-anthracen-9-yl)-pyrene (TP-AP-TP) were synthesized through boronylation and Suzuki coupling reactions. The Tg values of Ph-AP-Ph and TP-AP-TP were 228 °C and 243 °C, respectively, compared to values of 135 °C and 139 °C for the single core materials 9-(3′,5′-diphenylphenyl)-10-(3′′′,5′

In this study, four emitters of blue light are synthesized by selecting pyrene with its high photoluminescence quantum yield (PLQY) as the core group and variants of the electron-donating diphenylamine (DPA) as side groups. The four compounds have different numbers, sizes, and substitution positions of alkyl groups on the DPA. Each of the four compounds when doped in OLED devices shows a high current efficiency (CE) of over 7 cd A^-1 and a high external quantum efficiency (EQE) of over

Deep blue emitting materials with a new core structure containing indenopyrazine have been synthesized; a non-doped device using one of these materials as a blue emitter was found to exhibit high external quantumn efficiency of 4.6% and excellent color purity of (0.154, 0.078) as well as narrow emission band of 47 nm FWHM.

New hole injection layer (HIL) materials for organic light-emitting diodes (OLEDs) based on phenothiazine and phenoxazine were synthesized, and the electro-optical properties of the synthesized materials were examined by UV−vis and photoluminescence spectroscopy, and by cyclic voltammetry. 10,10′-bis(4- tert -butylphenyl)- N 7, N 7′-di(naphthalen-1-yl)- N 7, N 7′-diphenyl-10H,10′H-3,3′-biphenoxazine-7,7′-diamine (1-PNA-BPBPOX) showed glass transition temperatures ( T g ) of 161 °C, which was hig

Abstract We report three highly efficient multiresonance thermally activated delayed fluorescence blue-emitter host materials that include 5,9-dioxa-13b-boranaphtho[3,2,1- de ]anthracene (DOBNA) and tetraphenylsilyl groups. The host materials doped with the conventional N 7 , N 7 , N 13 , N 13 ,5,9,11,15-octaphenyl-5,9,11,15-tetrahydro-5,9,11,15-tetraaza-19b,20b-diboradinaphtho[3,2,1- de :1’,2’,3’- jk ]pentacene-7,13-diamine ( ν -DABNA) blue emitter exhibit a high photoluminescence quantum yield

This study not only describes the synthesis and characterization of a novel indenofluorene derivative, 6,6,12,12-tetraethyl-2,8-bis-[1,1′;3′,1′]terphenyl-4′-yl-6,12-dihydro-indeno[1,2-b]fluorine (TP-EIF), for use as an emitting material in blue organic light emitting diodes (OLEDs), but also the comparison with 6,6,12,12-tetraethyl-2,8-bis-[1,1′;3′,1′]terphenyl-4′-yl-6,12-dihydro-diindeno[1,2-b;1′,2′-e]pyrazine (TP-EPY). UV-visible and PL spectra showed that the TP-EPY absorption and emission ba

Deep-blue emitters based on phenanthro[9,10-d]oxazole (PO) and anthracene moiety for non-doped fluorescenct OLEDs.

The chrysene group, with its large band gap and high stability, was selected as a central core structure for ultra-deep-blue emitters. The effects of different side groups on the intrinsic properties of the chrysene core were systematically investigated.

The wavelength of excimer formation and efficiency of an OLED device were controlled through the change of the center position of the triple-core chromophore.

White emission with two sharp strong peaks - a molecular emission peak at 455 nm and an excimer emission peak at 591 nm - was obtained by introducing a terphenyl group into a highly twisted core chromophore, which promoted a molecular orientation in the film state suitable for excimer formation.

Using 4,9-dibromopyrene as a key intermediate, two new fused-core compounds, TP-PFF and TP-PFC-TP, were synthesized. These compounds not only exhibited excellent thermal stability but also yielded superior electroluminescence (EL) devices with a lower turn-on voltage, over 50% greater efficiency, and over 3 times longer lifetime than did a similar compound lacking a fused core. This new core-forming method can be applied in various applications with many different core groups.