Donghee Shin

Synthesis and property of diazocine derivatives substituted with imidazole in various positions

ABSTRACT TIACA-I, TIACA-II were synthesized by changing the substitution position of the imidazole group in the diazocine core. TIACA-I, TIACA-II in the film state showed absorption in the range of 354 to 392 nm and exhibited blue photoluminescence (PL) emissions at 448 and 462 nm, respectively. The PL wavelength of TIACA-II is red-shifted by 14 nm than that of TIACA-I due to the electron-donating intensity depending on the position of the imidazole group. The use of TIACA-II in a non-doped OLED device resulted in blue emission with current efficiency of 2.84 cd/A and CIE of (0.15, 0.18).

Synthesis and Electroluminescence Properties of New Type Multi-Chromophore Emitting Materials for Organic Light-Emitting Diodes

New three emitting compounds, AK-1, AK-2 and AK-3 including diazocine moiety were synthesized through Suzuki-coupling reaction. Physical properties such as optical, electroluminescent properties were investigated. UV-visible spectrum of AK-1, AK-2 and AK-3 in film state showed maximum 392, 393 and 401 nm. PL spectrum of AK-1, AK-2 and AK-3 showed maximum emission wavelength of 472, 473 and 435 nm. Three compounds were used as EML in OLED device: ITO/2-TNATA (60 nm)/NPB (15 nm)/EML (35 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). AK-3 OLED device showed C.I.E value of (0.18, 0.26) and luminance efficiency of 0.51 cd/A at 10 mA/cm2. New derivatives including diazocine moiety were introduced as OLED emitting material and the EL efficiency was increased by the proper combination of core and side group.

Synthesis and Electroluminescent Properties of New Dibenzo-Diazocine Derivatives

AK-1NA and AK-2NA based on dibenzo-diazocine and anthracene moieties were designed and synthesized. Normalized UV-visible spectra of AK-1NA and AK-2NA in film state showed maximum absorption wavelength of 394 and 393 nm. PL spectra of AK-1NA and AK-2NA showed maximum emission wavelength of 429 and 444 nm. At a current density of 10 mA/cm2, OLED devices of AK-1NA and AK-2NA exhibited luminance efficiency of 2.39 and 1.50 cd/A, power efficiency of 1.01 and 0.81 lm/W. Also, OLED devices of AK-1NA and AK-2NA devices exhibited CIE(x, y ) of (0.16, 0.22) and (0.23, 0.42).

Synthesis and property of diazocine derivatives substituted with imidazole including various chromophores

ABSTRACT The new diazocine derivatives, 2,8-bis(4-(1-(4-(10-(naphthalene-2-yl)anthracen-9-yl)naphthalene-1-yl)-1H -phenanthro[9,10-d]imidazol-2-yl)phenyl)-6H, 12H-5,11-methanodibenzo[b,f][1,5]diazocine (NANIDZ-I) and (5S,11S)-2,8-bis(4-(1-(4-(10-(naphthalen-1-yl)anthracen-9-yl)naphtha-lene-1-yl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-6H, 12H-5, 11-methanodibenzo[b,f][1,5]dizocine (NANIDZ-II) have been successfully synthesized and characterized. It has not only the characteristics of rigid, chiral and C2-symmetry but also charge transport capability and emission. NANIDZ-I and NANIDZ-II were synthesized by changing the substitution position of the imidazole group including various chromophore in the diazocine core. NANIDZ-I device in a non-doped organic light emitting diode resulted in blue emission with luminance efficiency of 4.29 cd/A and CIE of (0.17, 0.25).

Synthesis and electro-optical properties of diazocine derivatives based on different positions of substituted naphthyl group

ABSTRACT The new diazocine derivatives, 1-DAN and 2-DAN have been successfully synthesized and characterized. 1-DAN and 2-DAN, are different the positions of naphthyl substituted in the anthracene. In the film state, 1-DAN and 2-DAN exhibited absorption in the range of 354 to 402 nm and showed blue photoluminescence (PL) emission at 441 and 450 nm. The PL wavelength of 1-DAN was blue-shifted by 9 nm than that of 2-DAC. This is because the conjugation length is decreased by H atom-H atom repulsion between 1-naphthyl and anthracene. Organic light emitting diode (OLED) device using 2-DAN as emitting layer (EML) showed current efficiency of 1.76 cd/A.

New anthracene derivatives including diazocine for blue emitting materials

ABSTRACT The new anthracene derivatives including diazocine, (5S,11S)-2,8-bis(10-phenylanthracen-9-yl)-6,12-dihydro-5,11-ethanodibenzo[b,f][1,5]diazocine (AK-P) and (5S,11S)-4,4′-((6,12-dihydro-5,11-methanodibenzo[b,f][1,5]diazocine-2,8-diyl)bis(anthracene-10,9-diyl))-dibenzonitrile (AK-PCN) have been successfully synthesized and characterized. The ultraviolet-visible (UV-Vis) absorption of AK-P and AK-PCN showed in the range of 354 to 393 and exhibited maximum photoluminescence (PL) emissions at 458 and 463 nm, respectively in the film state. This slight red-shift in PL spectra of AK-PCN may be due to the polarity of the CN, electron withdrawing group. Using the AK-P as an emitting layer (EML), a non-doped organic light emitting diode (OLED) device resulted in blue emission with current efficiency of 1.37 cd/A and C.I.E. of (0.20, 0.25). AK-P exhibited a higher EL efficiency than that of AK-PCN.

New carbazole derivatives including coumarin moiety for blue emitting materials

ABSTRACT New carbazole derivatives including coumarin moiety, 7-(3-Carbazol-9-yl-phenyl)-chromen-2-one (C-PCa), 7-(9-Phenyl-9H-carbazol-3-yl)-chromen-2-one (PCa-C), 7-[9-(3-Carbazol-9-yl-phenyl)-9H-carbazol-3-yl]-chromen-2-one (PDCa-C) were synthesized by Suzuki reaction. A non-doped OLED was fabricated using the synthesized material as emitting materials. Among the three synthesized compounds, PDCa-C showed the highest efficiency with current efficiency of 1.34 cd/A and C.I.E of (0.18, 0.23) in the current density 10 mA/cm2.

Synthesis and property of diazocine derivatives substituted with carbazole in meta and para positions

ABSTRACT M-DAC and P-DAC have been successfully synthesized and characterized. The ultraviolet-visible (UV-Vis) absorption of M-DAC and P-DAC showed in the range of 373 nm to 394 nm and exhibited maximum photoluminescence (PL) emissions at 466 and 481 nm in the film state. PL wavelength of P-DAC is red-shifted by 15 nm than that of M-DAC. This is because carbazole is substituted for para position and the conjugation length is increased. M-DAC and P-DAC OLED devices exhibited current efficiency of 3.09 and 2.80 cd/A and C.I.E(x,y) values of (0.17, 0.27) and (0.18,0.33).

Synthesis and electroluminescence property of new type emitting materials including diazocine for OLEDs

ABSTRACT Four emitting compounds, namely, 2,8-Bis-(10-phenanthren-9-yl-anthracen-9-yl)-6H,12H-5,11-methano-dibenzo[b,f][1,5]diazocine(AK-4), 2,8-Bis-(10-pyren-1-yl-anthracen-9-yl)-6H,12H-5, 11-methano-dibenzo[b,f][1,5]diazocine(AK-5), 2-[10-(9,9-Dimethyl-9,9a-dihydro-4aH-fluoren-2-yl)-anthracen-9-yl]-8-[10-(9,9-dimethyl-9H-fluoren-2-yl)-anthracen-9-yl]-6H,12H-5,11-methano-dibenzo[b,f][1,5]diazocine(AK-6) and 2,8-Bis-[10-(spiro-fluroene)-anthracen-9-yl]-6H,12H-5,11-methano-dibenzo[b,f][1,5]diazocine(AK-7) were synthesized through Suzuki-coupling reaction. Physical properties such as optical, electroluminescent properties were investigated. UV-Visible spectrum of AK-4, AK-5, AK-6 and AK-7 in film state showed maximum 372, 374, 372 and 373 nm. PL spectrum of AK-4, AK-5, AK-6 and AK-7 showed maximum emission wavelength of 437, 451, 445 and 493 nm. Four compounds were used as EML in OLED device: ITO/2-TNATA(60 nm)/NPB(15 nm)/EML(35 nm)/Alq3(20 nm)/LiF(1 nm)/Al(200 nm). AK-6 OLED device showed C.I.E. value of (0.16, 0.20) and luminance efficiency of 2.67 cd/A.

Synthesis and electroluminescent properties of new diazocine derivatives

ABSTRACT 4-methyl-7-(10-(pyren-1-yl)anthracen-9-yl)-2H-chromen-2-one (PAC), 7,7-(anthracene-9,10-diyl)bis(4- methyl-2H-chromen-2-one) (CAC), 7-Ant-hracen-9-yl-4-methyl-chromen-2-one (AC), and 7-(naphthalen-1-yl)-2H-chromen-2-one (NC) were synthesized through Suzuki aryl-aryl coupling reaction. Optical and electroluminescence (EL) properties were evaluated by UV-visible absorption, photoluminescence (PL) spectra, and EL devices. Synthesized compounds were used as an emitting layer (EML) in non-doped device with the following structures: ITO/2-TNATA (60 nm)/NPB (15 nm)/synthesized compounds (35 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). Non-doped devices showed luminance efficiency (L.E.) of 1.38, 1.03, 1.12, and 0.39 cd/A at a current density of 10 mA/cm2.