• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.19-26
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• 2017

Increasing global energy demand has resulted in an energy crisis. The dye sensitizer solar cell (DSSC) is an alternative source because of its ability to convert the sun's energy into electrical energy. Our aim was to determine the effect of synthesized Ni(II)-Chlorophyll for enhancing the efficiency of solar cells based DSSC. Complex compound Ni(II)-Chlorophyll was successfully synthesized as a dye sensitizer of $Ni(NO_3)_2.6H_2O$ and chlorophyll ligand with saponification method. Characterization results with spectrophotometer UV-Vis showed that the complex compounds of Ni(II)-Chlorophyll have a maximum wavelength of 295.00 nm, 451.00 and 665.00 nm. The bond between the ligand and metal appears in the vibration Ni-O at wave number $455.2cm^{-1}$. Complex compoun Ni(II)-Chlorophyll has a magnetic moment 7.10 Bohr Magneton (BM). The performance of complex compound Ni(II)-Chlorophyll as a dye sensitizer shows the value of short-circuit current (Jsc) at $3.00mA/cm^2$, open circuit voltage (Voc) at 0.15 V and the efficiency (${\eta}$) 0.20%.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.145.2-145.2
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• 2003

We have developed a silver staining method using a dye as a silver sensitizer. Dye staining is performed in combination with silver nitrate staining. Dye-silver staining shortens the time of silver staining (~1 hr) and improves the sensitivity better than that of silver diamine stain (1-10 ng) or comparable to that of silver nitrate stain with glutaraldehyde as a silver sensitizer. In dye staining (silver sensitizing step), it has been proven that the sensitivity is at least 4 times comparing with that of CBBR stain and staining time is about 45 min. (omitted)

• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.87-98
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• 1996

In this study, benzoxazolo carbocyanine dye was used as sensitizer for photographic emulsion, and the photographic characteristics were examined. The basic properties of sensitizer such as stability in various solvents were examined. The sensitizer was very stable in methanol, acetonitrile, acetone, dimethylformamide, and chloroform solution. Absorption spectra of benzoxazolo carbocyanine dye $2.5{\times}10^{-6}M$ and $5{\times}10^{-6}M$ concentrations in 10% aqueous methanol solutions containing $10^{-2}M$ potassium chloride show the monomer-J-aggregation characteristics. Compared to the absorption peak of the monomer in pure methanol solution, the red shifts of the monomer-J-aggregate peaks of benzoxazolo carbocyanine dye of $2.5{\times}10^{-6}M$ and $5{\times}10^{-6}M$ concentrations in 10% aqueous methanol solutions containing $10^{-2}M$ potassium chloride are 34nm respectively, and the sensitizing peak of benzoxazolo carbocyanine dye in photographic emulsion has red shift of 34nm. Therefore, if was concluded that benzoxazolo carbocyanine dye can be used as green sensitizing dye for the spectral sensitization of photographic emulsion.

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.3052-3058
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• 2014

In this article, we have designed and synthesized a novel donor-${\pi}$-acceptor (D-${\pi}$-A) type porphyrin-based sensitizer (denoted UI-5), in which a carboxyl anchoring group and a 9,9-dimethyl fluorene were introduced at the meso-positions of porphyrin ring via phenylethynyl and ethynyl bridging units, respectively. Long alkoxy chains in ortho-positions of the phenyls were supposed to reduce the degree of dye aggregation, which tends to affect electron injection yield in a photovoltaic cell. The cyclic voltammetry was employed to determine the band gap of UI-5 to be 1.41 eV based on the HOMO and LUMO energy levels, which were estimated by the onset oxidation and reduction potentials. The incident monochromatic photon-to-current conversion efficiency of the UI-5 DSSC assembled with double-layer (20 nm-sized $TiO_2$/400 nm-sized $TiO_2$) film electrodes appeared lower upon overall ranges of the excitation wavelengths, but exhibited a higher value over the NIR ranges (${\lambda}$ = 650-700 nm) compared to the common reference sensitizer N719. The UI-5-sensitized cell yielded a relatively poor device performance with an overall conversion efficiency of 0.74% with a short circuit photocurrent density of $3.05mA/cm^2$, an open circuit voltage of 0.54 mV and a fill factor of 0.44 under the standard global air mass (AM 1.5) solar conditions. However, our report about the synthesis and the photovoltaic characteristics of a porphyrin-based sensitizer in a D-${\pi}$-A structure demonstrated a significant complex relationship between the sensitizer structure and the cell performance.

• Journal of Powder Materials
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• v.12 no.1
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• pp.7-16
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• 2005

Dye-sensitized solar cells(DSSCs) have been under investigation for the past decade due to their attractive features such as high energy conversion efficiency and low production costs. The basis for energy conversion in the injection of electrons from a photoexcited stateof a dye sensitizer into the conduction band of the nanocrystalline $TiO_2$ semiconductor upon absorption of light. It is believed that the DSSC is one of the most promising technologies to solve the significant energy problems. In this article, the development trends and perspective of DSSCs were reviewed.

• Journal of the Korean Applied Science and Technology
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• v.14 no.2
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• pp.65-70
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• 1997

The symmetric naphthothiazolo carbocyanine is of industrial importance as red-sensitizing dye in the spectral sensitization of emulsion microcrystals in negative film-making. The stability on the solvents of naphthothiazolo carbocyanine dye was measured by UV-Vis spectrophotometer, and then all of solvents were stabilized sensitizer. The maximum absorption peak range in various solvents was $600nm{\sim}612nm$. But it was identified that only methanol can be used to photographic emulsion.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.279-282
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• 2011

Dye-sensitized solar cell (DSSC); an alternate energy source harvester has gained some attractive features such as high-energy conversion efficiency low production cost. Dye-sensitizer is a basic component of DSSC, which affecting the performance of the energy conversion efficiency. Current research has been focusing on development of high efficiency, metal-free dye-sensitizers, which would be more environmental friendly. We had successfully explored synthetic route to 6,6'-(1,2,5-oxadiazole-3,4-diyl)dipyridine-2,4-dicarboxylic acid (3A) which has been used as organic sensitizer. Investigation of light conversion efficiency (${\eta}$) of the compound uses standard measurement condition (one sun simulated irradiation, AM 1.5, 100 mW/$cm^2$) showed that it could reach 1.00% ($J_{SC}=2.63\;mAcm^{-2}$, $V_{OC}$=0.64 V and FF=0.59). Under the same conditions, the ruthenium complex (N719) gave the conversion efficiency as high as 4.02%($J_{SC}=10.50\;mAcm^{-2}$, $V_{OC}$=0.67V and FF=0.57).

• Analytical Science and Technology
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• v.11 no.1
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• pp.13-19
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• 1998

In the dye sensitization for the solar energy conversion with a photoelectrochemical cell containing allylthiourea, the time profile of the sensitized photocurrent showed a rise and fall with the irradiation time. The dye solution before and after irradiation was analyzed by means of spectroscopic methods. A new precipitation reaction between sensitizer and supersensitizer and photobleaching of the dye appeared to be involved in the decreased photocurrent.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2083-2086
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• 2011

• Journal of Photoscience
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• v.9 no.2
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• pp.409-411
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• 2002

In order to prevent side reactions due to free radical formation occurring in the reactions of singlet oxygen generated in solution phse, it was required that singlet oxygen is generated in gas phase from an apparatus of a solid-gas system. We have accomplished to construct an apparatus generating singlet oxygen in solid-gas system, which is composed of a flexible optical fibre tube connected by a dye-sensitizer probe containing rose bengal dye on polymer or inorganic material. Through the optical fibre tube visible light from a laser and an oxygen stream are passed into the sensitizer probe where singlet oxygen is generated. The determination of singlet oxygen was carried out by two methods. One involves the detection of the luminescence of singlet oxygen at 1268 mn and the other involves the chemiluminescence reaction of a dihydroisobenzofuran with singlet oxygen emitting luminescence at 456 nm.