• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2008년도 추계학술대회 논문집
• /
• pp.197-200
• /
• 2008

본 연구에서는 Ketjen black을 이용한 DSCs (Dye-sensitized solar cells)용 다공질의 $TiO_2$ nano-powder 제작기술을 제안한다. $TiO_2$ powder는 sol-gel연소법에 의해 Ti-isopropoxide와 2-propanol을 사용하여 제작되었으며, Ketjen black의 함량($0g{\sim}2g$)을 달리하여 제작된 $TiO_2$ nano-powder의 다공성과 입자의 크기 결정성등의 특성을 고찰하였다. 또한 이러한 $TiO_2$ powder를 paste로 만들어 다른 열처리 온도($100^{\circ}C{\sim}600^{\circ}C$)에서 $TiO_2$ 박막을 이용한 DSCs를 제작한 후 그 효율을 측정하였다. 그 결과 Ketjen black 1g을 함유시켜 만들어진 $TiO_2$ powder의 다공성과 입자 크기가 가장 우수한 것으로 FE-SEM의 측정결과 나타났으며 또한 이 때의 $TiO_2$ powder는 FT-IR의 측정 결과, Ti-O-Ti의 결합구조를 가진 성분과 $H_2O$ 성분으로 구성되어 있음을 알 수 있었다. 그리고 여러 온도에서 제작된 DSCs 실험 셀 중 $500^{\circ}C$의 열처리 공정을 거적 제작된 셀의 효율이 가장 높은 효율이 5.46%를 나타내고 있음을 확인할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2010년도 하계학술대회 논문집
• /
• pp.213-213
• /
• 2010

In this thesis, we studied to increased to solar conversion efficiency of DSSC (dye-sensitized solar cell) using nanocrystalline $TiO_2$ semiconductor. We are preparation of $TiO_2$ photoelectrode, assembly the DSSC and put a focus in analyses electrochemical properties of DSSC and using Silica powder in $TiO_2$ photoelectrode for increase light scattering effect and improved conversion efficiency. It attempt to investigate the morphology of the photoelectrode and photovoltaic effects using field emission scanning electron microscopy (FE-SEM) and photovoltaic properties under illumination with AM 1.5 simulated sunlight. We got 146 % enhanced power conversion efficiency when the optimal content of quartz glass powder was 5 wt.% than that another content.

• 공업화학
• /
• 제18권6호
• /
• pp.650-653
• /
• 2007

$SnO_2$가 도핑된 $TiO_2$ 분말을 tin (IV) bis(acetylacetonate) dichloride와 titanium diisopropoxide bis(acetylacetonate)를 출발물질로, 유기염료인 quinacridone을 첨가하여 합성하였다. 반응 전후 염료의 구조를 FT-IR로 관찰하였고, 입자의 모양과 형태 및 결정의 구조는 FE-SEM과 XRD 분석기로 알아보았다. 환경오염물질로 유기염료인 indigo carmine을 선택하여 관찰한결과, 아나타제 구조를 갖는 quinacridone이 첨가된 분말을 합성하여, 가시광선 영역에서 광분해 효과를 관찰할 수 있었다.

• 한국의류학회지
• /
• 제41권2호
• /
• pp.212-223
• /
• 2017

This research investigated the screen printing method for natural indigo dye on cotton fabric. We examined four types of thickening agents (arabic gum, guar gum, indalca, and CMC) based on their ability to retard the oxidation of natural indigo print paste while the paste remained on the screen frame. The results indicated that the retardation of arabic gum towards oxidation was the greatest among the four types of thickening agents. The highest K/S value of the printed cotton was observed with a dye concentration of 50g/L fermented indigo powder. The best printing results were obtained when the duration of dye efficiency was tested for the 10 minutes of the dye paste remaining on the screen with a thickening agent concentration of 26.56% that represented 530 cps viscosity. The test of colorfastness to washing and rubbing of the printed cotton resulted in grade 5, and the colorfastness to sunlight resulted in grade 4. Chinese traditional Naminwhapo printing was reproduced on cotton fabric using the natural indigo printing method derived from this study.

• Bulletin of the Korean Chemical Society
• /
• 제32권5호
• /
• pp.1579-1582
• /
• 2011

Alumina particles wrapped in few-layer graphene sheets were prepared by calcining aluminum nitride powders under a mixed gas flow of carbon monoxide and argon. The graphene sheets were characterized by powder X-ray diffraction (XRD), Raman spectroscopy, electron energy loss spectroscopy, and high-resolution transmission electron microscopy. The few-layer graphene sheets, which wrapped around the alumina particles, did not exhibit any diffraction peaks in the XRD patterns but did show three characteristic bands (D, G, and 2D bands) in the Raman spectra. The dye-sensitized solar cell (DSSC) with the alumina particles wrapped in few-layer graphene sheets exhibited significantly improved overall energy-conversion efficiency, compared to conventional DSSC, due to longer electron lifetime.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2004년도 International Symposium on Powder Materials and Processing
• /
• pp.104-105
• /
• 2004

• 한국염색가공학회지
• /
• 제20권6호
• /
• pp.42-50
• /
• 2008

The objective of this study is to investigate the efficacy of pomegranate hull colorant as a natural hair coloring dye. The extract of pomegranate hull was concentrated and freeze-dried to get colorant powder. Effect of dyeing condition and mordanting on the dye uptake of hair by using Al, Fe, Cu, Cr, Sn compounds, color change and colorfastness were explored. In addition, tensile strength was measured and the surface of the hair was observed. Dye uptake of hair measured by K/S value (400 nm) indicated that ionic bonding seems to be involved in the sorption of pomegranate colorant to hair. Maximum sorption was obtained at pH 3.5 and the concentration of 50% (on the weight of hair, o.w.h.). Acidic dyeing condition (pH $3.5{\sim}5.0$) showed yellow color however alkaline dyeing condition (pH $7{\sim}11$) gave reddish yellow color. Pomegranate hull colorant produced greyish brown color on hair and the hair mordanted with Fe showed dark brown color. Mordants except Fe did not increase dye uptake significantly. Mordants except Cu increased light fastness and mordants except Cr increased washing fastness level slightly. According to SEM observation and the tensile strength retention measurement, the mordant dyed hair gave more damage to hair by ultraviolet light and washing than the hair dyed without mordanting. Experimental results of K/S value and colorfastness(light and washing) supported that pomegranate hull colorant without mordanting can be used as a semi-permanent natural hair coloring dye.

• 한국염색가공학회지
• /
• 제22권1호
• /
• pp.71-76
• /
• 2010

In this study the optimum dyeing conditions and blocking effect of UV deodorization efficiency of Ligustrum japonicum Thunb were investigated. Colorants were water-extracted from Ligustrum japonicum Thunb fruit and freeze-drided to obtain colorants powder. The effects of dye concentration, dyeing temperature, dyeing time, and the number of dipping count were studied. Fastness to dry cleaning, rubbing, perspiration, and light were measured according to KS K 0644, KS K 0650, KS K 0715 and KS K 0700, respectively. In order to examine the dyeability according to dyeing conditions, reflectance of fabrics were measured by using UV/VIS spectrophotometer. The bath ratio was 1:20. Dyeing concentration was 100, 200, 300, 400 and 500% on the weight of fiber. Dyeing time was 20, 40, 60, and 80 minutes. Dyeing temperature was 20, 40, 60, 80, and $100^{\circ}C$. The infrared high pressure dying machine was used. As dyeing concentration increased, dye adsorption increased up to 400% and it slowed down. Dye uptake was increased with raising themperature up to $80^{\circ}C$ and it slowed down. Dye adsorption occurred rapidly at first 20 minutes and then it slowed down and reached almost maximum dye uptake at 60 min. Dye uptake increased by repeated dyeing. Therefore, it is considered that optimum dyeing condition is 400%(o.w.f.), $80^{\circ}C$, 60 min. And repeated dyeing improves dye uptake. Color fastness to dry cleaning and rubbing was good, but light fastness and perspiration fastness was not good. Blocking effect of ultraviolet radiation and deodorization efficiency was good.

• 한국의류산업학회지
• /
• 제6권6호
• /
• pp.778-784
• /
• 2004

The natural dyeing of silk fabric with natural gardenia blue powder was investigated. The sum of K/S values was increased with increasing the amount of gardenia powder up to 20%,(o.w.b.). The proper time, temperature and pH for the dyeing of silk fabric with gardenia blue powder were 60~80 minutes, $80^{\circ}C$ and pH 4, respectively. The B and BG colors were obtained according to various mordanting methods, mordants and mordant concentrations. The various colorfastness were not improved by mordanting. The colorfastness to light was poor, but the colorfastness to dry cleaning and washing were good.

• 한국염색가공학회지
• /
• 제23권1호
• /
• pp.21-27
• /
• 2011

The natural dyeing of cotton fabric with gardenia blue powder was studied. Cotton fabrics were treated with chitosan in order to increase K/S values and colorfastness. K/S values were increased with increasing the concentration of gardenia blue powder, dyeing time and temperature, and the lower pH of dye bath. In case of chitosan finishing, K/S values were increased, and ${\lambda}_{max}$ shifted to 600nm at 400nm. The wash fastness was improved, but the abrasion fastness was lowered in the case of wet rubbing.