• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.441-441
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• 2009

Dye-sensitized solar cells (DSSCs) have been widely investigated as a next-generation solar cell because of their simple fabrication process and low coats. The cells use a porous nanocrystalline TiO2 matrix coated with a sensitizer dye that acts as the light-harvesting element. The photo-exited dye injects electrons into the $TiO_2$ particles, and the oxide dye reacts with I- in the electrolyte in regenerative cycle that is completed by the reduction of $I_3^-$ at a platinum-coated counter electrode. Since $TiO_2$ porous film plays a key role in the enhancement of photoelectric conversion efficiency of DSSC, many scientists focus their researches on it. Especially, a high light-to-electricity conversion efficiency results from particle size and crystallographic phase, film porosity, surface structure, charge and surface area to volume ratio of porous $TiO_2$ electrodes, on which the dye can be sufficiently adsorbed. Effective treatment of the photoanode is important to improve DSSC performance. In this paper, to obtain properties of surface and dispersion as nitric acid treated $TiO_2$ photoelectrode was investigate. The photovoltaic characteristics of DSSCs based the electrode fabricated by nitric acid pre-treatment $TiO_2$ materials gave better performances on both of short circuit current density and open circuit voltage. We compare dispersion of $TiO_2$ nanoparticles before and after nitric acid treatment and measured Ti oxidized state from XPS. Low charge transfer resistance was obtained in nitric acid treated sample than that of untreated sample. The dye-sensitized solar cell based on the nitric acid treatment had open-circuit voltage of 0.71 V, a short-circuit current of 15.2 mAcm-2 and an energy conversion efficiency of 6.6 % under light intensity of $100\;mWcm^{-2}$. About 14 % increases in efficiency obtained when the $TiO_2$ electrode was treated by nitric acid.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.6
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• pp.819-827
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• 2000

The purpose of this study is to produce cotton fabric having improved dyeability and colorfastness as well as retaining the desirable durable press property. When cotton fabric was treated with additives, nitrogen content was increased as the additive concentration was increased. DP ratings and wrinkle recovery properties of BTCA treated cotton fabrics were greatly increased. But DP rating was lowered slightly by adding additives and wrinkle recovery property was decreased with the increase of additive concentration. Tensile strength was decreased by BTCA treatment but increased as additive concentration was increased. Various BTCA/additive treatments produced great affinity for reactive and acid dyes when dyebaths were adjusted at pH 3. It was showed that dyeability was increased as additive concentration was increased. The most effective additive for improving the dyeing properties of the crosslinked cotton was TEAㆍHCl. In case of reactive dye, there was almost no improvement on the dyeability of finished cotton by adding salt. Color fastness to washing and light of finished and dyed cotton were low except for the washfastness of reactive dye. Dyeing the BTCA/additive treated cotton fabrics with reactive dye had no effect on the physical properties.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.4
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• pp.466-475
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• 2011

The dyeing properties of protein fiber with pine needles colorants were studied through an investigation of the effect of dyeing conditions such as dye concentration, dyeing temperatures and time on dye uptakes, effect of mordants, and color change. In addition, the various colorfastness of dyed silk and wool fabrics were evaluated for practical use. The antimicrobial ability, ultraviolet-cut ability, and deodorant ability were also estimated. The dye uptake increased as the dyeing concentration increased and this enabled the obtainment of the Langmuir absorption isotherm. The dye uptake increased as the dyeing time and temperature increased. Pine needles colorants showed relatively good affinity to protein fiber and produced a yellow color. Post-mordanting was more effective than the pre-mordanting, and the dye uptake of fabrics improved by mordanting. Except for washing, the colorfastness of dyed fabrics showed a low rating. However, the colorfastness to light and the dry cleaning of fabrics mordanted with N.Cu, and the friction fastness of fabrics mordanted with Cu improved. The guide fabrics showed very good antimicrobial abilities of 99.9%; in addition, the ultraviolet-cut ability and deodorant ability improved in fabrics dyed with pine needles extracts.

• Journal of the Korea Fashion and Costume Design Association
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• v.3 no.1
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• pp.5-14
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• 2001

The study was about on the colorfastness of the natural vegetable dye. Impatient Balsamina was chosen as a speciesof the natural vegetable dye. It has a long history for Korean Women‘s grooming on the nail to be reddened, Actually those were very easy to gather and easy to extract the colors from the leaves and the flowers, Also Impatient Balsamina were abundant near our environment. So this was a cue as a natural dye for the wool fabric, This study was designed to testify the possibility of the Impatient Balsamina as a natural vegetable. First, 2 kinds of extracts from the Impatient Balsamina were prepared. Second, 2 kinds of mordants and 3 kinds of dyeing process were used. And the dyed wool fabric were evaluated the color index using Chroma Meter, the result was recorded as L$^*$, a$^*$, b$^*$ value(65.86, 16.40, 36.80). The effect of the mordants was more effective in Cr mordant than Al mordant in the color fastness and the color affinity. The very interesting results were in the colorfastness to the drycleaning, that was graded 4 to 5, but the colorfastness to light was low, graded 2. Impatient Balsamina was veryfied, it could be a natural vegetable dye for the wool fabric.

• Environmental Engineering Research
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• v.22 no.3
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• pp.312-319
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• 2017

The treatment of dyeing wastewater is not easy because dyes are mainly aromatic, heterocyclic compounds. The most effective technologies and methods to treat dyeing wastewater are costly and involve materials that are difficult to regenerate after use. Therefore, it is necessary to develop cost-effective, eco-friendly technologies to treat dyeing wastewater. The aim of this study was to investigate the removal of sulfur blue 11 (CI 53235) anionic dye using methyl esterified sericite (ME-sericite) adsorbents in an aqueous solution. The results are discussed in terms of the ME-sericite particle size, temperature, pH value and initial sorption rate according to the initial sulfur blue concentration. In addition, we analyzed the adsorption kinetics using a Pseudo-second-order model with the desorption and reusability. The methyl esterification caused a considerable increase in the specific surface area from 4.45 to $17.62m^2/g$. The ME-sericite adsorbents successfully removed > 98% of the sulfur dye in the aqueous solution. For the adsorption of 1 mg of sulfur dye, approximately 4.6 to 6.6 g/L ME-sericite were required. The desorption process was carried out by mixing a NaOH eluent to desorb 90.56% of the sulfur dye with 2 h of contact time. Thus, the ME-sericite is a promising adsorbent to treat dyeing wastewater due to its low dose requirement, high removal efficiency and inexpensive material.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.3
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• pp.14-19
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• 2010

Partial anodic oxidation of Ti-mesh with a wire diameter of ~200[${\mu}m$] produces self-aligned $TiO_2$ nanotube arrays (~50[${\mu}m$] in length) on Ti-mesh substrate. The electrolyte used for anodic oxidation was an ethylene glycol solution with an addition of 1.5 vol. % $H_2O$ and 0.2 wt. % $NH_4F$. A dye-sensitized solar cell utilizing the photoanode structure of $TiO_2$-nanotube/Ti-mesh was fabricated without a transparent conducting oxide (TCO) layer, in which Ti-mesh replaced the role of TCO. The 1.93[%] photoconversion efficiency was low, which can be attributed to both insufficient dye molecules attachment and limited electrolyte flow to dye molecules. The optimized nanotube diameter and length as well as the $TiCl_4$ treatment can improve cell performance.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1279-1280
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• 2008

A serious problem of the 21st century is the supply of energy resources. Reserves of fossil fuels are facing depletion: renewable energy resources must be developed in this era. Dye sensitized solar cells(DSC) have been very economical and easy method to convert solar energy to electricity. DSC can reach low costs in future outdoor power applications. However, to commercialize the DSC, there are still many shortages to overcome. When the DSC is commercialized in the near future, the productivity is an important factor. In the process of soaking in a dye, it usually takes 12${\sim}$24 hours. In this study, we varied the dye coloring temperature from 0$^{\circ}C$ to 60$^{\circ}C$. At the temperature of 40$^{\circ}C$, DSC cell showed the best performance. We also conducted the time variant experiment to reduce the manufacturing time. Counter electrode surface of DSC is deposited by RF magnetron sputtering under the conditions of Ar $2.8{\times}10^{-3}torr$, RF power of 120W and substrate temperature of 100$^{\circ}C$.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.5
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• pp.540-546
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• 2016

Besides high-efficient photovoltaics based on silicon, polymers, dye-sensitization and hybrid perovskite materials, biomimetic solar cells inspired by a leaf in nature has also been actively studied. As one example, a hydrogel based photovoltaics (HGPV) is a low-cost, environmentally friendly device and requires easy fabrication process. In this paper, the effect of hydroquinone additive on the performance of the HGPV is discussed. The photocurrent increases ~14 times upon the addition of hydroquinone into the agarose hydrogel medium. The photocurrent increase is maximum at the optimum dye concentration, while the photovoltage is barely affected by the dye concentration. The effect of the agarose content in the hydrogel and the types of dyes on the photocurrent is also investigated. Finally, it is shown that the photovoltaic performance of HGPV with hydroquinone can be drastically improved when $TiO_2$ film is deposited on the anode electrode.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.159-168
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• 2005

Dye-sensitized solar cells (DSCs) 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 is the injection of electrons from a photoexcited state of a dye sensitizer into the conduction band of the nanocrystalline $TiO_2$ semiconductor upon absorption of light. It is believed that the DSC is one of the most promising candidates for renewable energy sources. In this review, the development trends and perspectives of DSCs are investigated.

• Environmental Engineering Research
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• v.24 no.3
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• pp.513-520
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• 2019

In this investigation, nano ZnO was sonochemically synthesized by a novel method using a methionine precursor. A narrow size distribution (41-50 nm) of nano ZnO was achieved that was immobilized on perlite and applied as a catalyst in catalytic ozonation. The catalyst was characterized by fourier transform infrared spectroscopy, BET surface area, and field emission scanning electron microscope. The ozonation of recalcitrant Remazol black 5 (RB5) di-azo dye solution by means of the synthesized catalyst was investigated in a bubble column slurry reactor. The influence of pH values (7, 9, 11), catalyst dosage (8, 12, 15, $20g\;L^{-1}$) and reaction time (10, 20, 30, 60 min) was investigated. Although the dye color was completely removed by single ozonation at a higher reaction time, the applied nanocatalyst improved the dye declorination kinetics. Also, the degradation of the hazardous aromatic fraction of the dye was enhanced five-times by catalytic ozonation at a low reaction time (10 min) and a neutral pH. The second-order kinetics was best fitted in terms of both RB5 color and its aromatic fraction removal. The total organic carbon analysis indicated a significant improvement in the mineralization of RB5 by catalytic ozonation using the nano-ZnO/perlite catalyst.