• 한국재료학회지
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• 제1권4호
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• pp.206-213
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• 1991

PbO 77-80wt%, ZnO 4.5-6wt%, $B_2O_3$ 7.5-8.5wt%, $TiO_2$ 3-7wt%, $P_2O_5$ 0.5-2wt%의 조성을 갖는 IC Package봉착용 저융점($400-460^{\circ}C$) 결정화유리 frit를 제조하였다. DTA-TMA, X-선 회절분석, SEM 등을 이용하여 봉착용 유리의 결정화 특성을 연구하였다. $TiO_2$ 함량이 3wt% 함유시료는 $420-440^{\circ}C$에서 $2PbO{\cdot}ZnO{\cdot}B_2O_3$의 결정이 균일성장하였다. $TiO_2$ 함량이 4wt% 첨가된 시료는 $420-440^{\circ}C$에서 $2PbO{\cdot}ZnO{\cdot}B_2O_3와\;PbTiO_3$ 결정이 섞여서 혼합결정을 이루고 있었다. 또한 $TiO_2$ 5wt% 첨가된 시료는 $440-460^{\circ}C$에서 perovskite $PbTiO_3$ 결정만 석출되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.103-106
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• 1997

The electrical properties and the sensing properties of ZnO-TiO$_2$ composites were investigated by using the complex impedance measurement and voltage-current source and measurement unit. In air, the electrical conductivity of TiO$_2$ added ZnO increase with increasing the content of TiO$_2$ and the relative dielectric constants for 3, 5 and 7mol% TiO$_2$ added ZnO are 7, 13 and 120, respectively. In 3000ppm CO gas, the relative dielectric constants for 3, 5mol% TiO$_2$ added ZnO are 25, 28, respectively.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.366-366
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• 2011

이성분 산화물인 ZnO/$TiO_2$ core-shell 나노입자는 core-shell 구조의 특성과 이성분 산화물의 상호작용에 의해서 염료감응형 태양전지의 효율향상을 기대할 수 있다. Znic acetate($Zn_2(CH_3COO)$)와 Titanium(IV) butoxide($Ti(OBu)_4$)를 이용하여 ZnO 나노입자를 수열합성하고 그 주의에 $TiO_2$을 가수분해 반응을 이용하여 둘러싸는 core-shell형태의 물질을 합성하였다. 그 이후 결정성 및 유기물 제거를 위해서 4시간 동안 고온에서 소성하였다. SEM 결과에 따르면 소성 온도를 600도까지 증가시키면 ZnO의 경우 나노입자의 크기가 증가하는 경향을 확인하였다. 하지만 core-shell의 경우는 ZnO의 뭉침현상을 $TiO_2$이 방해하여 초기합성된 크기와 동일한 크기를 유지하는 것을 확인하였다. 또한 XRD 결과에 따르면 주변에 형성된 $TiO_2$ 이외에 $Zn_2TiO_4$의 spinel 구조를 가지는 물질이 합성되는 것을 확인할 수 있었다. 합성된 core-shell 구조의 나노입자는 약 40~50 nm의 크기를 가지고 600도에서 소성된 입자의 경우 산소 정공이 거의 없는 약 3 eV의 밴드갭을 가지는 물질로 합성이 되었다. Core-shell 나노입자의 경우 염료 감응형 태양전지의 반도체 물질로 응용 가능할 것으로 판단된다.

• 한국세라믹학회지
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• 제36권10호
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• pp.1108-1114
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• 1999

Microstructure and electrical properties of ZnO-doped (0-5 mol%) 0.05 Pb(Mn1/3Sb2/3)O3-0.95 PZT ceramics were investigated. Sintering temperature was decreased to 100$0^{\circ}C$ due to eutetic reaction between PbO and ZnO. Grain-size increased up to adding 1mol% ZnO and then decreased. Compositions of grain and grain-boundary were investigated by WDS. Lattice parameter was decreased with ZnO addition. Density increased with ZnO addition and reached to the maximum of 7.84(g/cm2) at 2 mol% ZnO. The effect of ZnO on electrical properties of PMS-PZT was investigated. At 3mol% ZnO addition electromechanical coupling factor(kp) was about 50% and relative dielectric constant($\varepsilon$33/$\varepsilon$0) was 997 Mechanical quality factor(Qm) decreased with ZnO addition. Lattice parameters and tetragonality(c/a) were measured to investigate relationship between the electric properties and substitution of Zn2+. At 3 mol% ZnO tetragonality was maximiged at c/a=1.0035 Curie temperature (Tc) decreased slightly with ZnO addition.

• 한국세라믹학회지
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• 제14권3호
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• pp.187-192
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• 1977

For the purpose researching to the influence of tetrahedral and octahedral preference of cations of $Ni^{2+}$, $Ti^{4+}$ upon the formation and the color development of the $ZnO-SnO_2$ spinel containing $Ni^{2+}$ and $Ti^{4+}$ ions, the gradual substitution of $Ni^{2+}$ ions for $Zn^{2+}$ ions and of $Ti^{4+}$ ions for $Sn^{4+}$ ions of the spinel in NiO-ZnO-$SnO_2$-$TiO_2$ system was carried out. On samples prepared by calcining the oxide and basic cabonate mixtures at $1300^{\circ}C$ for 2 hours, the X-ray analysis, measurement of reflectance and the test of their stabilaity as a glaze pigment were also carried out. The results are summarized as follows 1) Single spinel was formed completely to x=1 in the $xNiO\cdot(2-x)ZnO\cdot{SnO}_2$system, and gave brilliant lightgreen hue. Moreover, $NiO\cdot{ZnO}\cdot{SnO}_2$ formed easily spinel than $NiO\cdot{MgO}\cdot{SnO}_2$ because Zn^{2+}$ ions had more strong tetrahedral preference than $Mg^{2+}$ ions. 2) As the gradual substitution of $Ti^{4+}$ ions for $Sn^{4+}$ ions in $NiO\cdot{MgO}\cdot{SnO}_2$ system, the spinels formed well and was nearly not changed in the hue. 3) The results of glaze test. (1) As the gradual substitution of $Ni^{2+}$ ions for $Zn^{2+}$ ions, the color changed from dull white to graish broun gradually in calcium-zinc glaze and calcium glaze, and from white to beige in tile glaze. (2) As the gradual substitution of $Ti^{4+}$ ions for $Sn^{4+}$ ions in $NiO-ZnO-SnO_2-TiO_2$ system, the color was become dull generally and was not change in tile glaze.

• 청정기술
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• 제21권1호
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• pp.39-44
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• 2015

본 연구에서는 다섯 종의 씨앗(춘채, 아욱, 양배추, 배추, 당근)을 이용하여 금속산화물 나노입자(CuO, NiO, Fe₂O₃, Co₃O₄, TiO₂, ZnO)들이 씨앗발아와 발아지수에 미치는 영향을 조사하였다. CuO, ZnO, NiO 나노입자는 씨앗 활성에 뚜렷한 독성 영향을 나타내었으며, 나노입자종류에 따라 상이한 민감도를 나타내었다. 각 나노입자에 대한 독성순서(EC₅₀ 범위)는 다음과 같다: CuO 6~27 mg/L > ZnO 16~86 mg/L > NiO 48~112 mg/L. 나머지 조사 대상 나노입자인 Co₃O₄, TiO₂, Fe₂O₃은 최대 1,000 mg/L 높은 농도 노출에도 뚜렷한 영향을 나타내지 않았다. 씨앗별 상이한 민감도를 나타내었으며, 가장 민감한 종인 아욱의 씨앗발아 EC₅₀은 CuO 5.5 mg/L ZnO 16.4 mg/L, NiO 53.4 mg/L로 조사되었다. 씨앗별 나노입자에 대한 독성 영향은 CuO > ZnO > NiO > Fe₂O₃ ≈ Co₃O₄ ≈ TiO₂ 나타났으나, 당근씨앗은 NiO [EC₅₀ 80.4(71.41~90.54) mg/L]와 ZnO [EC₅₀ 85.8(69.31~106.29) mg/L]가 유사한 독성을 나타내었다.

• 한국재료학회지
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• 제32권2호
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• pp.94-97
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• 2022

We fabricated 3 types of ETL, mp TiO₂, ZnO, and ZnO coated on mp TiO₂(ZMT) to compare the photoelectric conversion efficiency (PCE) and fill factor (FF) of Perovskite solar cells. The structure of the cells was FTO/ETL/Perovskite (CH₃NH₃PbI₃)/spiro-MeOTAD/Ag. SEM morphology assessment of the ETLs showed that mp TiO₂ was porous, ZnO was flat, and the ZMT porous surface was filled with a thin layer. Via XRD measurements, the crystal structures of mp TiO₂ and ZnO ETL were found to be anatase and wurtzite, respectively. The XPS patterns showing energy bonding of mp TiO₂, ZnO, and ZMT O 1s confirmed these materials to be metal oxides such as ETL. The electrical characteristics of the Perovskite solar cells were measured using a solar simulator. Perovskite solar cells with ZMT ETL showed showed PCE of 10.29 % than that of conventional mp TiO₂ ETL devices. This was considered a result of preventing Perovskite from seeping into the ETL and preventing recombination of electrons and holes.

• 한국결정성장학회지
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• 제1권1호
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• pp.107-116
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• 1991

초음파 진동자를 사용 분무 열분해시켜 $Pb(NO_3)_2$와 $TiO(NO_3)_2$ 용액으로부터 $PbTiO_3$ 미분말을 합성하고 미립자의 특성을 조사하였다. 또한 미립자 형성과정을 같은 방법으로 합성되어 문헌에 보고된 $BaTiO_3$, $ZrO_2$, ZnO 등의 미립자 형성과정과 비교 검토하였다.

• 한국세라믹학회지
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• 제28권11호
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• pp.897-907
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• 1991

This study was conducted to research the formation and the color development of CoO-ZnO-Fe2O3-TiO2-SnO2 system for the purpose of synthesizing the spinel pigments which are stable at high temperature. After preparing CoO-ZnO-Fe2O3, in which CoO causes the color, as a basic composition, $\chi$CoO.(1-$\chi$)ZnO.Fe2O3 system, $\chi$CoO.(1-$\chi$)ZnO.TiO2 system and $\chi$CoO.(1-$\chi$)ZnO.SnO2 system were prepared with $\chi$=0, 0.2, 0.5, 0.7, 1.0 mole ratio respectively. The manufacturing was carried out at 128$0^{\circ}C$ for 90 minutes. These specimens were analyzed by the reflectance measurement and the X-ray diffraction analysis and the results were summarized as follows: 1. All of the specimens formed the spinel structure and were colored with stable yellow or blue. 2. As the content of CoO and Fe2O3 in the specimens being increased, the reflectance of each specimen was measured becoming lower and the colors were changed from yellow to greyish blue and from blue to dark blue. 3. As the substituting amount of Co2+ ion for Zn2+ ion in $\chi$CoO-ZnO-TiO2-SnO2 system being increased, the colors were changed from blue to greyish blue. The colors were changed from yellow to grayish green owing to the tetrahedral Co2+ ions being increased, the octahedral Co2+ ions being decreased with increasing the amount of Sn4+ ions. 4. CoO-ZnO-Fe2O3-TiO2-SnO2 system, in which Zn2+ was substituted with Co2+ and Fe3+ was substituted with Ti4+ and Sn4+, easily formed the spinel structure without regard to the amount of substitution or the ion owing to the selectivity of the coordination number: 4 of Zn2+, 4 of Co2+, 6 of Fe3+ or 6 of Ti4+ and Sn4+.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.963-967
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• 2001

The effects of the sintering additives such as Bi$_2$O$_3$and V$_2$O$_{5}$ on the microwave dielectric and sintering properties of ZnTiO$_3$system were investigated. Densities of >97% of the theoretical densities have been attained for ZnTiO$_3$at the sintering temperature range of 870~90$0^{\circ}C$ with Bi$_2$O$_3$and V$_2$O$_{5}$ additions of $_3$were obtained with 0.6wt% Bi$_2$O$_3$and 0.5wt% V$_2$O$_{5}$; Qxf$_{o}$ = 48,400 GHz, $\varepsilon$$_{r}$ = 22, and $\tau$$_{f}$ = -43 PPm/$^{\circ}C$. In order to improve temperature coefficient of resonance frequency, TiO$_2$was added to the above system. The optimum amount of TiO$_2$was 15mo1% when sintered at 87$0^{\circ}C$, at which we could obtain following results ; Qxf$_{o}$ = 44,700 GHz, $\varepsilon$$_{r}$ = 26, and $\tau$$_{f}$ = 0 ppm/$^{\circ}C$.EX>.>.EX>.>.>.EX>.