• 분석과학
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• 제19권5호
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• pp.376-382
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• 2006

In this work, pitch/activated carbon/$TiO_2$ composite were prepared by $CCl_4$ solvent method with different mixing ratios. The BET surface area of pitch/activated carbon/$TiO_2$ composite has a significantly increase with increasing activated carbon content in pitch/activated carbon/$TiO_2$ composite. The surface structure and elemental compositions of the composite were studied by SEM and EDX, respectively. The SEM results were presented to the characterization of porous texture on the pitch/activated carbon/$TiO_2$ composite. And EDX data was shown the presence of C, O, S, Ti and other elements. The structural properties of the composite were studied in XRD measurements. The $TiO_2$ crystal phases of the pitch/activated carbon/$TiO_2$ composite had lots of rutile-type structure which transforms from anatase-type with a little of anatase-type structure. The photocatalytic activities of the composite were evaluated using a photo-decomposition method under UV lamp. The pitch/activated carbon/$TiO_2$ composites were observed better photocatalytic activity than that of pristine $TiO_2$.

• KSBB Journal
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• 제6권4호
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• pp.425-429
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• 1991

이상의 실험 결과로부터 다음과 같은 결과를 얻었다. 1. $TiO_2-SiO_2-AL_2O_3-B_2O_3-CaO-Na_2O$계에서 분상을 일으켰을 때 $600^{\circ}C$, 6시간 열처리시켰을 때 최대의 비표면적을 나타냈다. 2. 저온에서 열처리 시간이 증가하면 비표면적은 증가하고 고온에서는 열처리 시간이 증가하면 비표면적은 감소하다가 다시 증가한다. 3. 상분리 및 비표면적은 열처리 시간보다 열처리 온도에 더욱 민감하였다.

• 한국재료학회지
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• 제16권3호
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• pp.178-182
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• 2006

A single electro-discharge-sintering (EDS) pulse (1.0 kJ/0.7 g), from a $300{\mu}F$ capacitor, was applied to atomized spherical Ti-6Al-4V powder in a low vacuum to produce porous-surfaced implant compacts. A solid core surrounded by a porous layer was formed by a discharge in the middle of the compact. XPS (X-ray photoelectron spectroscopy) was used to study the surface characteristics of the implant material. C, O, and Ti were the main constituents, with smaller amounts of Al, V, and N. The implant surface was lightly oxidized and was primarily in the form of $TiO_2$ with a small amount of metallic Ti. A lightly etched EDS implant sample showed the surface form of metallic Ti, indicating that EDS breaks down the oxide film of the as-received Ti-6Al-4V powder during the discharge process. The EDS Ti-6Al-4V implant surface also contained small amounts of aluminum oxide in addition to $TiO_2$. However, V detected in the EDS Ti-6Al-4V implant surface, did not contribute to the formation of the oxide film..

• 한국결정성장학회지
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• 제2권2호
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• pp.11-19
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• 1992

$SrTiO_3$미분말은 초음파 분무 열분해법으로 chloride와 nitrate 수용액을 출발용액으로 사용하여 농도를 0.05M과 0.1M로 하였으며 각 농도에 따른 유속의 변화를 0.5cm/sec로 변화시켜 합성하였다. 분말의 형성 과정은 0.05M, 0.05cm/sec 조건에서 단계별 분말을 합성하여 주로 morphorlogy 측면에서 고찰하였다. 출발용액이 chloride 수용액인 경우 SrTiO$_3$미분말을 합성할 수 없었으며 nitrate 수용액인 경우 모든 조건에서 (110)면을 주 peak로 하는 cubic의 순수한 구형의 $SrTiO_3$미분말을 얻을 수 있었다. 평균입자의 크기는 유속이 증가함에 따라 $0.49{\mu}m$에서 $0.55{\mu}m$로 증가하였다. 출발액적의 크기는 $14.3{\mu}m$이었으며 단계별 입자의 형태는 1, 2단계에서 용매의 증발에 의해 매우 porous하였으며 불규칙하였고, 3, 4, 5단계를 지나는 동안 점차 둥근 형태로 형성되었다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2000년도 추계학술대회
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• pp.173-177
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• 2000

인산염계 5Li₂O, 36CaO, 20TiO₂, 27P₂O/sub 5/의 조성을 선정하여 10K/min 승온속도로 1300℃에서 2시간동안 유지시켜 모유리를 제조하였고, 최적의 핵형성을 위해 610℃에서 20시간, 최고 결정성장을 위해 840℃에서 20시간 동안 열처리함으로써 LiTi₂(PO₄)₃상과 β-Ca₃(PO₄)₂결정상이 존재하는 Glass Ceramics를 제조하였고, 이를 1N-HCI용액에서 3일간 담지하여 β-Ca₃(PO₄)₂결정상을 용출시켜 LiTi₂(PO₄)₃상만이 존재하는 다공성 Glass Ceramics를 제조하였다.

• 한국재료학회지
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• 제18권5호
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• pp.229-234
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• 2008

Porous Ti implant samples were fabricated by the sintering of spherical Ti powders in a high vacuum furnace. To increase their surface area and biocompatibility, anodic oxidation and a hydrothermal treatment were then applied. Electrolytes in a mixture of glycerophosphate and calcium acetate were used for the anodizing treatment. The resulting oxide layer was found to have precipitated in the phase form of anatase $TiO_2$ and nano-scaled hydroxyapatite on the porous Ti implant surface. The porous Ti implant can be modified via an anodic oxidation method and a hydrothermal treatment for the enhancement of the bioactivity, and current multi-surface treatments can be applied for use in a dental implant system.

• 한국전기전자재료학회논문지
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• 제27권11호
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• pp.746-752
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• 2014

Photo electrode is an important component of DSSC, so this paper did some research on it. Through the method of adding PEG additive into $TiO_2$ paste, the electrical characteristics and efficiencies of DSSCs with photo electrode surface area were studied. In the case of not adding PEG in $TiO_2$ paste, $26{\mu}m$ thickness $TiO_2$ photo electrode shows 5.081% efficiency. The highest short circuit current density was $10.476mA/cm2^$. The structure of porous $TiO_2$ film can be controlled through changing the PEG additive amount in $TiO_2$ paste and the molecular weight of PEG. When the additive amount of PEG 20,000 in $TiO_2$ paste reaches 5%, the peak efficiency with $26{\mu}m$ thickness $TiO_2$ photo electrode was 5.387% and its highest current density were $11.084mA/cm^2$.

• Bulletin of the Korean Chemical Society
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• 제23권3호
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• pp.477-480
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• 2002

A new microporous TiO2-pillared layered titanate has been successfully prepared by hybridizing the exfoliated titanate with the anatase TiO2 nano-sol. According to the X-ray diffraction analysis and N2 adsorption-desorption isotherms, the TiO2-pillared layered titanate showed a pillar height of ~2 nm with a high surface area of ~460 m2/g and a pore size of ~0.95 nm, indicating that a microporous pillar structure is formed. Its photocatalytic activity was evaluated by measuring the photodegradation rate of 4-chlorophenol during irradiation of catalyst suspensions in an aqueous solution. An enhancement in activity of ca. 170% was obtained for TiO2-pillared layered titanate compared to that of the pristine compound such as layered cesium titanate.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.130-131
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• 2020

This study manufactured the porous foamed concrete granules coated with TiO₂ Nanoparticles, to widen the specific surface area. The Removal rate of concrete granules coated with TiO₂ Nanoparticles was average 56.7%, which was approximately 2.3 time higher than that of the conventional surface TiO₂ coating.

• 전기학회논문지
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• 제58권2호
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• pp.327-331
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• 2009

Nano-porous $TiO_2$ powder was fabricated using Acetylene black, applied photo voltaic device based on the Dye-sensitized Solar Cells (DSCs) was investigated experimentally. $TiO_2$-powder was fabricated using Ti-isopropoxide and 2-propanol by sol-gel combustion method. For cases of variable Acetylene black, characteristic of porosity, size of particle and crystallite of obtained $TiO_2$ nano-powder was investigated. The photovoltaic efficiency of the prepared DSCs was measured using $TiO_2$ film which prepared on each different heat treatment temperature($400^{\circ}C{\sim}700^{\circ}C$) with paste of $TiO_2$ powder. The porosity and size of particle of $TiO_2$ powder made with Acetylene black 0.4g was influenced significantly effect to DSCs characteristic. Heat treatment at $500^{\circ}C$ makes the better photovoltaic efficiency which 5.02%($J_{sc}=11.79mA/cm^2$, $V_{oc}=0.73V$, ff=0.58). The sol-gel combustion method was useful to DSCs fabrication.