• 한국세라믹학회지
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• 제33권7호
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• pp.793-801
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• 1996

Sol-gel법으로 제조한 $PbTiO_3$ 세라믹스 박막의 결정화거동, 미세구조 및 유전특성에 있어서 무촉매, 산성촉매 및 염기성촉매가 미치는 영향에 관하여 연구하였다. 열처리온도에 따른 페로브스카이트로의 상전이는 염기성 촉매를 첨가하였을 때가 가장 빨랐으며, 미세구조의 균일성 및 유전특성은 $HNO_3$ 산성촉매를 사용하였을 때가 가장 우수하였다. 그러나, 촉매에 관계없이 $Si_{(100)}$ \ $SiO_2$ \Pt 기판을 사용하였을 때에는 75$0^{\circ}C$ 이상의 고온에서 Pb의 휘발이 급격하게 일어나 제 2상의 생성 및 미세구조가 불균일하게 번화함으로써 물성저하를 피할 수 없었다.

• Korean Journal of Chemical Engineering
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• 제35권12호
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• pp.2452-2463
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• 2018

Surface treatment of sol-gel bioglass is required to increase its biomedical applications. In this study, a dielectric barrier discharge (DBD) plasma treatment in atmospheric pressure was performed on the surface of [$SiO_2-CaO-P_2O_5-B_2O_3$] sol-gel derived glass. The obtained bioglass was treated by plasma using discharge current 12 mA with an exposure period for 30 min. The type of discharge can be characterized by measuring the discharge current and applied potential waveform and the power dissipation. Apatite formation on the surface of the DBD-treated and untreated samples after soaking in simulated body fluid (SBF) at $37^{\circ}C$ is characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), inductively coupled plasma (ICP-OES) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). We observed a marked increase in the amount of apatite deposited on the surface of the treated plasma samples than those of the untreated ones, indicating that DBD plasma treatment is an efficient method and capable of modifying the surface of glass beside effectively transforming it into highly bioactive materials.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.769-772
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• 2004

We report on the developed fabrication method of lanthanide-doped xerogel/porous anodic alumina structures for an image formation via the aluminum anodization, the sol-gel synthesis, and the photolithography process. The structures of europium- or terbium-doped xerogel/porous anodic alumina are also considered in view of application in electroluminescent devices.

• 한국세라믹학회지
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• 제41권9호
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• pp.670-676
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• 2004

플라즈마 디스플레이(Plasma Display Panel)의 도전성 전극 성형에 필요한 잉크젯용 은 나노 졸을 합성하고자, 액상 환원법에 의해 고농도의 은 나노 졸의 입자크기 및 입도분포와 분산성을 제어하였다 이를 위하여 생성된 입자에 분산성을 부여하는 고분자 전해질의 착체형성 비율과 함께 은 나노 졸의 고농도화를 진행하였다. 합성된 졸은 XRD, 입도분포측정기, TEM을 사용하여 상분석 및 입자의 크기와 형상을 관찰하였다 그 결과 분산성이 우수하고, 약 10nm의 입자크기를 갖는 은 나노 졸인 것을 확인할 수 있었으며, 10-40wt% 범위의 고농도 은 나노 졸을 합성할 수 있었다.

• 대한치과보철학회지
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• 제44권5호
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• pp.617-627
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• 2006

Statement of problem: HA has been used as a coating material on Ti implants to improve osteoconductivity. However. it is difficult to form uniform HA coatings on implants with complex surface geometries using a plasma spraying technique. Purpose : To determine if Ti6Al4V sintered porous-surfaced implants coated with HA sol-gel coated and hydrothermal treated would accelerate osseointegration. Materials and Methods : Porous implants which were made by electric discharge were used in this study. Implants were anodized and hydrothermal treatment or HA sol-gel coating was performed. Hydrothermal treatment was conducted by high pressure steam at $300^{\circ}C$ for 2 hours using a autoclave. To make a HA sol, triethyl phosphite and calcium nitrate were diluted and dissolved in anhydrous ethanol and mixed. Then anodized implant were spin-coated with the prepared HA sols and heat treated. Samples were soaked in the Hanks solution with pH 7.4 at $37^{\circ}C$ for 6 weeks. The microstructure of the specimens was observed with a scanning electron microscope (SEM), and the composition of the surface layer was analyzed with an energy dispersive spectroscope (EDS). Results : The scanning electron micrographs of HA sol-gel coated and hydrothermal treated surface did not show any significant change in the size or shape of the pores. After immersion in Hanks' solution the precipitated HA crystals covered macro- and micro-pores The precipitated Ca and P increased in Hanks' solution that surface treatment caused increased activity. Conclusion : This study shows that sol-gel coated HA and hydrothermal treatment significantly enhance the rate of HA formation due to the altered surface chemistry.

• 자원리싸이클링
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• 제16권5호
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• pp.31-35
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• 2007

본 연구에서는 소디움실리케이트로부터 실리카 솔의 형성과 성장에 관한 연구를 고찰하였다. 황산으로 소디움실리케이트 수용액을 산화시킬 때 실리카 함량은 2%가 적절하였으며, 수용액 내 나트륨 이온 제거 후 안정한 실리케이트 수용액을 얻기 위해서는 수용액 pH를 9 이상 유지하여야 한다. 소디움실리케이트와 실리케이트 수용액을 혼합하여 pH 10으로 유지하여 $80^{\circ}C$로 가열하여 10 nm 크기의 실리카 솔을 제조할 수 있었다. 또한 실리케이트 용액을 실리카 솔 용액에 첨가하여 실리카 솔을 50 nm로 성장시킬 수 있었다.

• 한국재료학회지
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• 제9권12호
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• pp.1181-1187
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• 1999

diol을 기반으로 하는 Sol-Gel 방법으로 PZT (53/47) 1M sol 용액을 만들어 회전 코팅법으로 Pt/Ti/$SiO_2$/Si 기판위에 코팅하였고 한번 코팅으로 최대 0.9${\mu}m $의 PZT막을 얻었다. PZT는 비강유전성 pyrochlore상을 거쳐 강유전성 perovskite상으로 전이하며 따라서 PZT perovskite seed가 상전이에 미치는 영향을 규명하고자 하였다. 0.2${\mu}m $ 이하의 크기를 갖는 1wt% PZT분말을 propanol용액에 분산시켜 PZT sol 용액에 도입하여 seeded PZT 막을 제조하였다. Seeded PZT막을 열처리한 결과 perovskite상의 생성이 촉진되어 상전이 온도가 50$^{\circ}C$정도 낮아졌다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2003년도 추계학술발표회초록집
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• pp.69-70
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• 2003

• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 추계학술발표강연 및 논문개요집
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• pp.120-120
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• 1998

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1997년도 Proceedings of the 13th KACG Technical Meeting `97 Industrial Crystallization Symposium(ICS)-Doosan Resort, Chunchon, October 30-31, 1997
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• pp.13-19
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• 1997

From the formation of the monodispersed silica particle which is a valuable for the industry by Sol-Gel process, the effects of the parameters participated in the process, the growth mechanism and the characteristics of silica particles for each rection conditions are investigated. To investigate about the formation of final silica particles, the suspension which performs the polymerization is reacted with molybdic acid, and the evolutions of TEOS and silica particle size are investigated in the reaction time ？ 새 the characteristics of molybdic acid with the suspension. From the results, a constant number of silica particle is formed at early reaction stage. Silica particles grow through the aggregation of smaller particles and nucleation is rate-limiting step for the growth of particles. In the conditions of this study, spherical silica particles are formed, [NH$_3$] and [$H_2O$] concentration increase the particle size but particle size decrease with [$H_2O$] concentration which is a certain above region. Average particle sizes are 187.4~483.3 nm and standard deviations in the average particle size are 1.7~2.9% with each experimental condition. From the BET results, specific surface area is 5.5~23.4 $m^2$/g and these values decrease with increase size. The average pore size is 50~70$\AA$.