• 한국재료학회지
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• 제16권9호
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• pp.538-542
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• 2006

Nano-sized cobalt oxide powders were prepared by low pressure spray pyrolysis process. The precursor powders obtained by low pressure spray pyrolysis process from the spray solution with ethylene glycol had several microns size and hollow structure. The precursor powders obtained from the spray solution with optimum concentration of ethylene glycol formed the nano-sized cobalt oxide powders with regular morphology after post-treatment without milling process. On the other hand, the cobalt oxide powders obtained from the spray solution without ethylene glycol had submicron size and spherical shape before and after posttreatment. The mean size of the cobalt oxide powders formed from the spray solution with concentration of ethylene glycol of 0.7M was 180 nm after post-treatment at temperature of $800^{\circ}C$. The mean size of the powders could be controlled from several tens nanometer to micron sizes by changing the post-treatment temperatures in the preparation of cobalt oxide powders by low pressure spray pyrolysis process.

• Progress in Superconductivity
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• 제5권1호
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• pp.65-69
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• 2003

Many researches on fabrication process for BSCCO precursor powders have been developed for high J$_{c}$ BSCCO-2223 tape. Spray pyrolysis method for fabrication of precursor powder has many advantages, such as high purity, fine particle size and low carbon content of BSCCO precursor powder. Fine, spherical powders were prepared by ultrasonic spray pyrolysis from the aqueous solution of metal nitrates. BSCCO precursor powders were synthesized with various solutes concentration and heat treatment conditions. Average particle size for spray pyrolysis powders was $1.5∼3\mu\textrm{m}$. Bi-2223/Ag tape was prepared by PIT method and followed by various sintering conditions. BSCCO precursor powders were characterized by XRD, SEM, EDS, Carbon content and particle size analysis.s.

• Korean Chemical Engineering Research
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• 제44권3호
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• pp.235-242
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• 2006

분무 열분해법이란 전구체를 용해시킨 용액을 수 마이크론에서 수십 마이크론 크기의 액적으로 분무한 후, 용매를 증발시키고 석출된 전구체를 열분해하여, 입자 및 필름을 제조하는 공정이다. 이 분무 열분해법의 핵심 요소는 전구체,용매, 액적 제조 그리고 분해 반응기 등 4가지이다. 이 4가지 요소의 적절한 조합에 의해서 현존하는 거의 대부분의 입자와 필름을 제조할 수 있는 범용성이 높은 기술이다. 현재 기술 수준으로는 상업적인 성공을 거두기는 힘들지만 향후 다성분계의 입자나 필름, 혹은 고기능성 입자의 제조에 응용될 경우 매우 유용한 기술로 각광을 받을 전망이다. 본 총설에서는 이 분문 열분해법을 이용해서 만들어지는 입자 중에서 주로 형광체를 중심으로 지금까지 개발된 다양한 분무 열분해 공정 기술을 소개한다

• 반도체디스플레이기술학회지
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• 제21권3호
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• pp.22-25
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• 2022

Metal oxide semiconductor (MOS) based on spray-pyrolysis deposition technique has attracted large attention due to simple and low-cost processibility while preserving their intrinsic optical and electrical characteristics. However, their high process temperature limits practical applications. Here, we demonstrated the nc-ZnO/ZnO field-effect transistors (FETs) via spray-pyrolysis as incorporating ZnO nanocrystalline nanoparticles into typical ZnO precursor. The nc-ZnO/ZnO FETs exhibit good quality of electrical properties. Our experiments reveal that nc-ZnO in active layer enhance electrical characteristics.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2003년도 High Temperature Superconductivity Vol.XIII
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• pp.77-77
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• 2003

• 한국세라믹학회지
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• 제44권5호
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• pp.148-150
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• 2007

A process to synthesize $La_{0.8}Sr_{0.2}CrO_3$ (LSC), which is a promising material for use as a separator in a soild oxide fuel cell, is investigated in this study. LSC powders without secondary Phases could be synthesized with ultrasonic spray pyrolysis and a heat treatment at $1200^{\circ}C$ for 20 h; however, it showed an average diameter of $0.6{\mu}m$ with a wide particle size distribution. On the other hand, LSC powders synthesized with spray pyrolysis at $800^{\circ}C$, heat-treated at $900^{\circ}C$ for 5 h, ball-milled and finally heat-treated again at $1200^{\circ}C$ for 20 h showed a smaller average diameter of $0.3{\mu}m$ and narrower size distribution. Very few particles above $0.5{\mu}m$ were found. Thus, a proper combination of the heat treatment and milling process after spray pyrolysis it determined to be very important in synthesizing fine and uniform LSC perovskite powders.

• 한국진공학회지
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• 제5권4호
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• pp.341-347
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• 1996

Spray pyrolysis 방법으로 넓은 면적의 $Cu_2S$/CdS 태양전지를 제작하였다. 제작과정에서 전극형성, CdS spray 온도조건, $Cu_2S$층의 접합 조건등 태양전지의 효율에 영향을 주는 요인을 조사하였다. CdS 박막의 조건은 주사 전자현미경, X-선 회절기, 온도변화에 따른 광흡수 및 관전도 특성등을 통해 결정하였다. 1$\textrm{cm}^2$의 면적의 전지에 air mass 2(AM2)인 75mW/$\textrm{cm}^2$로 빛을 조사했을 때 3.15%의 효율을 얻었다.

• 한국재료학회지
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• 제24권1호
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• pp.25-32
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• 2014

In this study, nano-sized cobalt oxide powder with an average particle size below 50 nm was prepared from a cobalt chloride solution by the spray pyrolysis process. The influences of reaction temperature on the properties of the generated powder were examined. The average particle size of the particles formed based on the spray pyrolysis process at a reaction temperature of $700^{\circ}C$ is roughly 20 nm. Moreover, most of these particles cannot appear with an independent type, thereby coexisting in a droplet type. When the reaction temperature increases to $800^{\circ}C$, the average particle size not only increases to roughly 40 nm but also shows a more dense structure while the ratio of particles which shows a polygonal form significantly increases. As the reaction temperature increases to $900^{\circ}C$, the distribution of the particles is from roughly 70 nm to 100 nm, while most of the particle surface is more intricately close and forms a polygonal shape. When the reaction temperature increases to $1000^{\circ}C$, the particle size distribution of the powder shows an existing form from 80 nm to at least 150 nm in an uneven form. As the reaction temperature increases, the XRD peak intensity gradually increases, yet the specific surface area gradually decreases.

• Korean Journal of Chemical Engineering
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• 제35권12호
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• pp.2480-2486
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• 2018

Mesoporous $TiO_2$ microspheres were prepared by spray pyrolysis for photocatalysis. Post modification of $TiO_2$ by heat treatment was performed to optimize its photocatalytic performance. First, spherical $TiO_2$ particles with mesoporous structure were synthesized at pyrolysis temperatures of 500, 600, and $700^{\circ}C$. After characterization by XRD, SEM, and $N_2$ adsorption, a sample prepared at $500^{\circ}C$ was found to possess desirable properties for photocatalytic performance through post-modification. In methylene blue degradation, mesoporous $TiO_2$ microspheres synthesized at $500^{\circ}C$ outperformed other microspheres. Furthermore, samples obtained by spray pyrolysis at $500^{\circ}C$ were calcined at various temperatures as a post-modification process. The sample calcined at $350^{\circ}C$ showed improved photocatalytic activity due to optimal anatase crystallinity and surface area.

• 한국세라믹학회지
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• 제46권2호
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• pp.137-145
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• 2009

A remarkable improvement of the productivity in barium titanate by slurry spray pyrolysis process was realized by supplying solid source slurry into the rector. The produced barium titanate powders showed uniform powder properties, and reproducibility with higher tetragonality in the range of 80$\sim$200 nm, case by case. The secondary calcination experiments of the as-prepared powders by spray pyrolysis revealed that the powders as-prepared over 700$^{\circ}C$ showed perfectly different behavior with the lower temperature's ones and the solid state reaction’s case. The result was discussed in terms of the reaction mechanism based on the activation energy analysis.