• 한국세라믹학회지
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• 제34권10호
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• pp.1003-1008
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• 1997

The (La, Sr)MnO3 powder used as air-electrode material of Solid Oxide Cell (SOFC) was synthesized by Modified-GNP(Modified-Glycine Nitrate Process). The powders were prepared using oxide and carbonate stable in atmosphere and nitric acid was used as a solvent of starting material as well as an oxidant for combustion. The (La, Sr)MnO3 powders were synthesized with 0.5, 1, 2, 3, 4 of glycine/cation molar ratio. The ICP (Inductively Coupled Plasma Mass Spectrometer) result represented compositional equality between synthesized and desired powders. In case of 2 molar ratio, the as-synthesized powder showed perovskite phase and specific surface area were 19 $m^2$/g. After calcination of 85$0^{\circ}C$, the calcined powder except 0.5, 1 molar ratio of glycine to cation showed perovskite phase.

• 한국세라믹학회지
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• 제35권8호
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• pp.857-863
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• 1998

MLCC(Multilayer ceramic capacitor) 등의 전자 세라믹스 분야에서 폭넓게 이용되는 BaTiO3 분말 제조를 위해 GNP(Glycine-Nitrate process)법을 이용하였다. 일반적인 GNP법과는 달리 출발물질로 카보네이트와 알콕사이드를 도입했고, 연소반응의 산화제 및 출발물질의 용매로써 질산을 사용하였으며, 연소합성시의 연료인 글리신의 첨가량을 달리하여 분말을 합성하였다. 연소합성된 분말의 특성은 helium pycnometer, XRD, N2 흡착을 이용한 BET, 주사전자현미경 등으로 분석하였다. 제조된 전구체 분말은 100$0^{\circ}C$로 하소시에 단일상의 BaTiO3 상으로 전이되었으며, 조성이 1.2인 경우 24m2/g의 높은 비표면적 값을 나타내었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 추계학술발표강연 및 논문개요집
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• pp.137-137
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• 1999

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.91-95
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• 1999

PED용 형광체로 사용되는 ZnCa$_2$O$_4$를 Clycine Nitrate Process로 합성하여 고상 반응법으로 합성한 ZnCa$_2$O$_4$ 분말과 비교 분석하였다. 또한 Glycine Nitrate Process로 제조시 Mn의 doping 농도를 변화시키면서 각각의 조성비에 따른 발광특성을 알아보았다. TGA 측정 결과 GNP법으로 합성된 ZnCa$_2$O$_4$ 의 경우 약 40$0^{\circ}C$ 이상에서 무게감량의 변화가 없었으며, XRD 상분석 결과 연소반응 후 이미 상형성이 이루어짐을 알 수 있었다. PL측정을 결과 GNP(GIycine Nitrate Process)로 제조된 ZnCa$_2$O$_4$분말의 발광효율이 고상 반응법으로 제조된 분말보다 우수하였으며, 균일하고 비표면적이 큰 단일상임이 관찰되었고, 더 작은 에너지와 시간으로 제조할 수 있는 장점이 있었다

• 한국세라믹학회지
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• 제33권4호
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• pp.411-417
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• 1996

Ultrafine NiO/YSZ (Yttria Stabilized Zirconia) powders were made by using a glycine nitrate process which is used as anode material for solid oxide fuel cells. The specific surface areas of synthesized NiO/YSZ powders were examined with controlling pH of a precursor solution and the content of glycine. The binding of glycine with metal nitrates occurring in the precursor solution was analyzed by using FTIR. The characteristics of synthesized powders were examined with X-ray diffraction(XRD) Brunauer Emmett Teller with N2 absorption. scanning electron microscopy (SEM). and transmission electron microscopy (TEM). Ultrafine NiO/YSZ powders of 15-18 m2/g were obtained through GNP when the content of glycine was controlled to 1 or 2 times the stoichiometric ratio in the precursor solutions. Strongly acid precursor solution increased the specific surface area of the synthesized powders. This is suggested to be the increased binding of metal nitrates and glycine under a strong acid solution of pH=0.5 that lets glycine consist of mainly the amine group of {{{{ { NH}`_{3 } ^{+ } }}. After sintering and reducing treatment of NiO/YSZ powders synthesized by GNP the Ni/YSZ pellet showed ideal microstructure where very fine Ni particles of 3-5 ${\mu}{\textrm}{m}$ were distributed uniformly and fine pore around Ni metal particles was formed. leading to anincrease of the triple phase boundary among gas Ni and YSZ.

• 한국수소및신에너지학회논문집
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• 제18권1호
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• pp.46-51
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• 2007

LSM powder material for an oxygen-electrode(anode) of High Temperature Steam Electrolysis (RISE) was synthesized by a Modified-Glycine nitrate process(GNP). Amount of nitric acid and its concentration was varied to find out an appropriate composition for the oxygen-electrode(anode). In order to optimize the amount of Glycine used as an oxidant of self-combustion process, the ratio of Glycine to Anion was varied. $La_{0.8}Sr_{0.2}MnO_3$, $La_{0.5}Sr_{0.5}MnO_3$, and $La_{0.2}Sr_{0.8}MnO_3$ were synthesized in this study. Those LSM were dried for overnight to remove moisture from the material at $110^{\circ}C$ and were calcined 2 hours at $650^{\circ}C$ and were sintered in a furnace for 5 hours at $1400^{\circ}C$. Their structures, surface morphologies, surface areas, and weight changes were investigated with XRD, SEM, BET, and TG/DTA. The best perovskite phase for the oxygen-electrode of HTSE was obtained with $La_{0.8}Sr_{0.2}MnO_3$ formula in which 100 ml of 3M nitric acid was used in the preparation of its formula. The optimized ratio of Glycine to Anion was 2.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.137-141
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• 1999

금속 다층박막과 미세입상 합금박막에서 발견된 Giant Magnetoresistance(GMR) 현상에 고무되어 최근에는 50년대에 밝혀졌던 산화물 자기저항 재료에 관하여 새롭게 연구하고 있으며 perovskite 구조를 가지는 La$_{1-x}$ Ca/xub x/MnO$_{3}$ 박막에서 큰 자기저항을 얻었으며 이를 Colossal Magentoresistance (CMR) 이라 부른다. 본 연구에서는 La$_{1-x}$ Ca/xub x/MnO$_{3}$ 분말을 하소온도를 700-90$0^{\circ}C$로 변화시킨 고상반응법과 자발착화연소합성법(Glycine-Nitrate Process) 으로 각각 제조하였으며 비교 분석하였다. TG-DTA을 이용하여 불순물과 미반응 물질을 확인하여 적당한 하소 온도를 결정하였고 XRD를 이용하여 결정상을 분석하였다. 주사전자현미경(SEM)으로 각각 제조된 분말의 하소후 입자의 크기를 비교하였다. GNP법으로 합성한 경우가 고상반응법을 이용한 경우보다 입자의 크기가 submicron 단위로 미세하고 균질하며 고순도의 perovskite 구조를 갖는 La$_{1-x}$ Ca/xub x/MnO$_{3}$ 분말을 얻을 수 있었다.었다.

• 한국재료학회지
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• 제9권1호
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• pp.51-56
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• 1999

The $BaTiO_3$ powders were synthesized by GNP (Glycine-Nitrate process). The powders were prepared using carbonate and alkoxide as starting materials and nitric acid was used as a solvent for starting materials as well as an oxidant for combustion. the effects of aggregates in $BaTiO_3$ powders on green densities, sintering and dielectric characteristics were investigated. When the glycine/cation molar ratio was 1.2, reactivity of self-combustion was most intensive and the degree of aggregates after calcination was low. On sintering at $1400^{\circ}C$, maximum theoretical relative density(94.99%%0 was obtained in case of 1.2 molar ratio of glycine/cation. The dielectric constant of this sintered $BaTiO_3$ was 1919.

• 한국세라믹학회지
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• 제42권12호
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• pp.821-826
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• 2005

Gadolinia-doped ceria nanopowder was prepared by glycine-nitrate combustion method with different glycine/nitrate mixing ratio. The characteristics of the synthesized powder were investigated by X-ray diffraction method, transmission electron microscopy, thermal gravity, differential thermal analysis and thermo-mechanical analysis. The smallest powder was obtained with glycine/nitrate ratio 1.00 and the lowest organic and water vapor contained powder was made with glycine/nitrate ratio 1.75. According to dilatometry, fast densification was occurred around $1000^{\circ}C$ and shows full density over $1300^{\circ}C$. Finally near-fully dense ceria electrolyte was fabricated with conventional sintering technique. Glycine-nitrate process yields fine nanopowders which enable low temperature sintering and fabrication of fully dense and nanostructured oxide electrolyte.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.1080-1083
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• 2001

Ultrafine NiO/YSZ composite powders were prepared by using a glycine nitrate process for anode material of solid oxide fuel cells. The specific surface areas of synthesized NiO/YSZ composite powders were examined with controlling pH of a precursor solution and the content of glycine. The characteristics of synthesized composite powders were examined with X-ray diffractometer, a BET method with N$_2$absorption, scanning and transmission electron microscopy. The strongly acid precursor solution increased the specific surface area of the synthesized composite powders. This is suggested to be caused by the increased binding of metal ions and glycine under a strong acid solution of pH=0.5 that lets glycine consist of mainly the amine group of NH$_3$$\^$+/. After sintering and reducing treatment of NiO/YSZ composite powders synthesized by GNP, the Ni/YSZ pellet showed ideal micro-structure very fine Ni parties of 3-5${\mu}$m were distributed uniformly and fine pores around Ni metal particles were formed, thes, leading to an increase of the triple phase boundary among gas Ni and YSZ.