• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2279-2285
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• 2011

The geometries, electronic structures and absorption spectra of the two organic triphenylamine-based dyes TA-St-CA and TA-DM-CA, containing identical electron donors and acceptors but the different conjugated bridges, were studied by density functional theory (DFT) at the B3LYP and PBE1PBE levels, respectively. The influence of para-orientating methoxyl units on the electronic structures and light absorption properties of the dyes and the consequent photovoltaic performance of the dye-sensitized solar cells (DSSCs) were investigated in detail. The results indicate that the introduction of the para-orientating methoxyl units into the conjugated bridge induces the increased absorption wavelength as well as the more negative EHOMO corresponding to the bigger driving force $(E_{I^-/I^-_3}-E_{HOMO})$ for dye reduction, which together improve the photovoltaic performance of TA-DM-CA, although there is a decline of the open circuit voltage caused by the more negative $E_{LUMO}$.

• Journal of Photoscience
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• v.5 no.1
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• pp.45-46
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• 1998

The green-sensitive silver halide emulsion layer has been studied UV-Vis absorption band of 9-methvl-5,5'-diphenyl-3,3'-bis(3-sulfopropyl)benzoxazolo carbocyanine triethyl ammonium salt in methanol solution and 10% methanol containing 10$^{-2}$ M KCl. the products were observed at 502nm and 540nm(J-band), respectively. The maximum spectral sensitivity of sensntizing silver halide emulsion showed at 546nm. In conclusion, benzoxazolo carbocyanine dye can be used as a green-sensitizing dye for the photographic emulsion.

• Textile Coloration and Finishing
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• v.3 no.1
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• pp.25-27
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• 1991

New Series of diazaanthraquinone near-infrared dye was synthesised by the ring closure reaction between 2,3-dibromodiazaanthraquinone and potassium 2-aminobenzenethiololate. This dye absorbs near-infrared light at 780 nm.

• Korean Journal of Materials Research
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• v.24 no.9
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• pp.458-464
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• 2014

Light scattering enhancement is widely used to enhance the optical absorption efficiency of dye-sensitized solar cells. In this work, we systematically analyzed the effects of spherical voids distributed as light-scattering centers in photoanode films made of an assembly of zinc oxide nanoparticles. Spherical voids in electrode films were formed using a sacrificial template of polystyrene (PS) spheres. The diameter and volume concentration of these spheres was varied to optimize the efficiency of dye-sensitized solar cells. The effects of film thickness on this efficiency was also examined. Electrochemical impedance spectroscopy was performed to study electron transport in the electrodes. The highest power conversion efficiency of 4.07 % was observed with $12{\mu}m$ film thickness. This relatively low optimum thickness of the electrode film is due to the enhanced light absorption caused by the light scattering centers of voids distributed in the film.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.2
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• pp.45-61
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• 2015

In order to analysis on color difference of natural dyes, I have dyed Hanji, cotton, silk fabric and exposed them to carbon arc light. The results of experiment have been analysed by wavelength of maximum absorption, amounts of dye uptake, color difference, Hunter's value and Munsell's value. Gardenia Jasminoides is monogenetic dye, but it gained darker color by pre-mordanting method used Al mordant agent and greenish yellow color by Fe mordant agent. whereas Curcuma, an Amur cork, and bud of pagoda tree are shown as greenish yellow color, and A barberry root, Betel nut, and Rhubarb are shown as reddish yellow color. these gained khaki colored dyed fabric by Fe mordanting. In addition, Sappan wood showed great result in pre-mordanting. Especially, it gained dark red color by Al pre-mordanting. The pink color was shown by post-mordanting. and Logwood showed great dyeing result in Hanji and cotton better than silk. Specially pre-mordanting was effective. Hanji and cotton showed greenish blue color by Al pre-mordanting, and silk showed brown color.

• Textile Coloration and Finishing
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• v.27 no.4
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• pp.261-269
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• 2015

Two new D-${\pi}$-A dyes were synthesized by the condensation reaction between active methyl and aromatic aldehyde and its biothiol sensing properties in DMSO/water were investigated by UV-vis spectroscopy. Upon addition of $Hg^{2+}$, the solution of D-${\pi}$-A dyes showed color change and the absorption band shows a formation of a dye-$Hg^{2+}$ coordination complex. These dyes exhibited high selectivity for $Hg^{2+}$ as compared with other cations. The dye-$Hg^{2+}$ could be recovered by adding glutathion(GSH). The absorption intensity of dye-$Hg^{2+}$ increased only by the addition of glutathione(GSH). The competition experiments revealed that no obvious interference was observed by performing the titration with the mixture of glutathione(GSH) and other amino acids. The results indicated that these D-${\pi}$-A dyes were highly selective for glutathione(GSH) detection.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2269-2279
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• 2009

Six metal-free organic dyes having thiophene (1), benzene-thiophene (2), thiophene-benzene (3), thiophene-pyridine (4), thiophene-thiophene (5), and pyridine (6) linkers between 9,9-dimethylfluorenyl terminal group and $\alpha$-cyanoacrylic acid anchor were synthesized. Among them, organic dye 5 showed the longest ${\lambda}_{max}$ value (424 nm) in UV-Vis absorption spectrum, better incident monochromatic photon-to-current conversion efficiency (IPCE), highest short circuit photocurrent density ($J_{SC},\;9.33\;mA^2/cm^2$), and highest overall conversion efficiency ($\eta$, 3.91%).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.35-39
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• 2016

In this research, we focused on the improvement of cy3 dye's characteristics for LCD color filter. Solubility and thermal stability are main characteristics of dyes for LCD color filter. We performed experiment to change counter cation of cy3 dyes with alkoxy substituent for these purposes. These cy3 dyes (1b~5b) were prepared through the synthetic procedure of three steps. The synthesized new cy3 dyes were charaterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed purple color and maximum absorption wavelength (${\lambda}_{max}$) in the range of 578~590 nm in UV/Vis spectrum. We confirmed that solubility and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with alkoxy substituent have good solubility in organic solvents such as dichloromethane, methanol, and acetone. Especially, Cy3 dye with 4-nitrobenzyl counter cation (5b) gave excellent solubility characteristics.

• Textile Coloration and Finishing
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• v.5 no.3
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• pp.216-220
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• 1993

Dissociation constants and heat of dissociation of dimers of 3, 3'-diethyl-thiacarbocyanine dye(Dye 2) have been studied. At $10~40^{\circ}C$, absorption spectra of 2 vol% aqueous ethanol solutions of Dye 2 showed monomer and dimer bands. From the temperature dependence of monomer absorbance, dissociation constants K and ${\Delta}H$ were estimated to be $6.2(10^{\circ}C)-10.6(40^{\circ}C)mon/\ell$ and 3kcal/mol, respectively. These K valus are about one half of those for 3,3'-diethyl-2,2'-cyanine dye with one methine carbon, indication a higher dimer stability than that of 3,3-diethyl-2,2'-cyanine dye.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.119.2-119.2
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• 2011

Dye-sensitized solar cells (DSSC) are currently attracting wide spread academic and commercial interest for the conversion of sunlight into electricity because of their easy manufacturing process and high efficiency. The solar energy conversion efficiencies of DSSC are strongly dependent on dye molecules adsorbed on the TiO2 surface which used for photosensitization of sun light, since an excited state of dye could inject an electron into the conduction band of semiconductor. We have developed novel organic dyes which have phenothiazine moieties as an electron donor in their charge-transfer chromophore for application of DSSCs. We had synthesized a series of phenothiazine derivatives which have different wave length absorbing chromophore in the molecule with high molar extinction coefficient. The photovoltaic performance of DSSC composed of organic chromophores with broad wavelength absorption property were measured and evaluated by comparison with that of pristine ruthenium dye.