• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.671-674
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• 2003

Generally, $TiO_2$ powders absorb ultraviolet rays and make oxidation/reduction reactions on its surface. Hydroxide radical(OH), a product of photocatalyst reactions, has so strong oxidation/reduction electric potential that it can oxidize noxious gas like NOx. In this study, $TiO_2$ was substituted for cement to investigate the purifying degree of NOx. Rutile and anatase types of $TiO_2$ were used as photocatalyst. The sun rays and the ultraviolet were used as a light source. Anatase type $TiO_2$ was better than rutile type in purifying performance. The sunray showed the best purifying performance among the light sources. 3% substitution of TiO$_2$ with the sunray was enough to purify NOx efficiently.

• 한국표면공학회지
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• 제53권4호
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• pp.153-159
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• 2020

Photocatalytic decomposition of polyethylene film with TiO₂ nanotube powders (NTs) was investigated under UV irradiation at ambient conditions. TiO₂ NTs composed of individual nanotubes are prepared by rapid breakdown anodization technique. A comparative study on the photocatalytic decomposition of polyethylene-TiO₂ composite films prepared using TiO₂ nanoparticles (NPs) or TiO₂ NTs (NTs), respectively, was conducted under UV irradiation. Polyethylene film incorporated with TiO₂ NTs showed 26 wt% weight loss after 200 h under UV irradiation about two times faster decomposition rate than TiO₂ NPs which is attributed to large surface area of TiO₂ NTs.

• 한국재료학회지
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• 제6권3호
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• pp.282-290
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• 1996

광화학 반응의 초기 유발을 위한 광촉매로 TiO2가 가장 널리 알려져 있으며, 기존의 상품보다 광촉매 활성도가 높은 촉매를 얻기 위해 Sol-Gel법을 이용하였다. TiO2 광촉매 제조를 위하여 전구체로서 Tetra-eth해-ortho-titanate(TEOT)를 이용하여 xerogeol 분말을 얻었으며, 광화학 반응의 효율을 측정하기 위해 분해대상 물질을 Dichloroacetic acid(DCA)로 선정하였다. 순수 titania 졸을 얻기 위한 최적조건은 알콕사이드 1몰당 물 40몰, 산 0.05몰이었고 pH의 범위는 3.3-3.6이었으며 Hexylene Glycol(HG)의 첨가량은 1몰임을 알 수 있었다. BET-N2방법을 이용하여 표면적을 측정한 결과 물/알콕 사이드의 몰비가 40-80범위에서 비표면적이 급격히 증가되어 DCA 의 광분해율도 증가하였으며, 몰 40몰을 첨가 후 졸-겔법으로 제조한 분말을 40$0^{\circ}C$에서 1시간 열처리한 anatase phase의 TiO2가 최고의 광분해 효율인 약 21%를 보였다. 이는 상업용으로 가장 효율이 높은 Dagussa P-25의 DCA 분해 효율보다 2배 정도 높은 것으로 나타났다.

• 대한화학회지
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• 제37권1호
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• pp.92-97
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• 1993

졸-겔법은 양질의 유리와 결정화 유리를 합성할 수 있는 새로운 방법이다. 알코올 용액에서 $Ba(OG)_$ 와 Ti[OCH(CH_3)_2]$를 반응시켜 강유전성 물질인 티탄산 바륨 분말을 합성하였다. 이 분말을 열중량 분석한 결과 전체적으로 약 16.5%의 중량 감소가 있었다. $700^{\circ}C$에서 2시간 동안 열처리하여 정방정의 티탄산 분말을 얻었으며 이때 비표면적이 $16.0m^2/g$였다. 소결에 의한 수축을 측정한 결과 $1100^{\circ}C$ 부근에서 시작되었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권6호
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• pp.291-296
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• 2006

In this study, the sputtered BTO film was polished by CMP process with the self-developed $BaTiO_3$- and $TiO_2$-mixed abrasives slurries (MAS), respectively. The removal rate of BTO ($BaTiO_3$) thin film using the $BaTiO_3$-mixed abrasive slurry (BTO-MAS) was higher than that using the $TiO_2$-mixed abrasives slurry ($TiO_2$-MAS) in the same concentrations. The maximum removal rate of BTO thin film was 848 nm/min with an addition of $BaTiO_3$ abrasive at the concentration of 3 wt%. The sufficient within-wafer non-uniformity (WIWNU%) below 5% was obtained in each abrsive at all concentrations. The surface morphology of polished BTO thin film was investigated by atomic force microscopy (AFM).

• 한국분말재료학회지
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• 제15권1호
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• pp.13-17
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• 2008

Visible-light responsive $TiO_2$:Zr, N powders were prepared by polymer complex solution method and the particle properties were characterized by using transmission electron microscope, BET method, X-ray diffractometer and UV-Vis spectrophotometer. The photocatalytic reactivity of the catalysts was also estimated by analyzing NO degradation. Polyhedral $TiO_2$ powder having about 20 um in the average particle diameter was successfully prepared, The XRD analysis revealed that the as-prepared powder consisted of anatase and rutile phases. The light absorption of the as-prepared $TiO_2$:Zr, N powder was shifted to the visible light. In addition, the as-prepared $TiO_2$:Zr, N nanoparticles showed the higher photocatalytic activity than the commercial $TiO_2$ under both UV and visible lights.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.26.2-26
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• 2003

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.80.2-80
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• 2003

• 한국세라믹학회지
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• 제26권5호
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• pp.691-697
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• 1989

Fine TiO2 and BaTiO3 powders having spherical particles were synthesized by ultrasonic spray pyrolysis of alcoholic solution of metal alkoxide in an electric furnace heated at 400-90$0^{\circ}C$. Microstructure and composition of particles synthesized were observed by TEM and XRD respectively. Spectific surface area of powders synthesized was examined through BET specific surface area measurement. TEM observation revealed that the particle size did not change irrespective of pyrolysis temperature but decreased according to the increase of concentration and spherical particle was consisted of primary particles of about 0.02${\mu}{\textrm}{m}$. As for BaTiO3 powder, the ratio of Ti/Ba was 0.987 by EDX analysis.

• 한국세라믹학회지
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• 제36권7호
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• pp.691-697
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• 1999

TiO2 powder was adsorbed on the surface of mica using the heterocoagulation method in water TiO2 powder was prepared from hydrolysis of titanium-iso propoxide in a mixed solvent of anhydrous ethanol and water. When the molar ratio of water to titanium iso-propoxide was 0.25 monodispersed spherical TiO2 particles were obtained. The prepared TiO2 powder showed anatase phase after heat treatment at 50$0^{\circ}C$ for 2 h and then transformed to rutile phase after heat treatment at 100$0^{\circ}C$ for 2h. The iso-electric points of TiO2 and Mica were pH 3.9 and pH 3.25 respectively which were measured by the Z-potential analysis in water base. The maximum Z-potential difference between two powders was observed in the range of pH 3.6~3.7 TiO2 powder was adsorbed on the surface of mica by heterocoagulation method in pH 3.6~3,7 The properties of prepared TiO2 powder was haracterized by TG-DTA, XRD and SEM The morphology and thermal properties of TiO2-adsorbed mica were examined.