• Title, Summary, Keyword: ZnO addition

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The Effect of ZnO Addition on the Electric Properties and Microstructure of $Pb(Mn_{1/3}Sb_{2/3})O_3-Pb(Zr_{0.52}Ti_{0.48})O_3$Ceramics ($Pb(Mn_{1/3}Sb_{2/3})O_3-Pb(Zr_{0.52}Ti_{0.48})O_3$계 세라믹스의 전기적 특성과 미세구조에 미치는 ZnO 첨가영향)

  • 김민재;최성철
    • Journal of the Korean Ceramic Society
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    • v.36 no.10
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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.

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Effect of CuO and $Al_2O_3$ Addition on the Electrical Conductivity of ZnO (ZnO의 전기전도도에 미치는 CuO 및 $Al_2O_3$의 첨가영향)

  • 전석택;최경만
    • Journal of the Korean Ceramic Society
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    • v.32 no.1
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    • pp.106-112
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    • 1995
  • In order to examine the effect of CuO and Al2O3 addition on the electrical conductivity of ZnO, both Al2O3 (0, 1, 2, 5, 10at.%) and CuO (1, 5at.%) were added to ZnO. Al2O3 addition (~2at.% Al) increased the total electrical conductivity of ZnO which was already decreased by CuO doping effect Above solid solubility of Al (~2at.%), ZnAl2O4 formed and the total electrical conductivity decreased due to the decrease of sintered density. Impedance measurements were used to know the reason and degree of contribution of three resistive elements, ZnO grain, ZnO/CuO, and ZnO/ZnO grain boundaries, to the total electrical conductivity changed.

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Piezoelectric Properties of lead free (Na0.44K0.52)Nb0.84O3-Li0.04(Sb0.06Ta0.1)O3 Ceramics with ZnO Addition (ZnO 첨가량에 따른 비납계 (Na0.44K0.52)Nb0.84O3-Li0.04(Sb0.06Ta0.1)O3 세라믹스의 압전 특성)

  • Lee, Dong-Hyun;Lee, Seung-Hwan;Nam, Sun-Pill;Lee, Young-Hie
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.11
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    • pp.2021-2025
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    • 2010
  • Electrical and structural properties were investigated on the effects of ZnO and the lead-free NKN-LST ceramics with the addition of ZnO were fabricated by a conventional mixed oxide method. A gradual change in the crystal and microstructure was observed with the increase of ZnO addition. For the NKN-LST-ZnO ceramics sintered at $1050^{\circ}C$, bulk density increased with the addition of ZnO and showed maximum value at addition 2.0mol% of ZnO. Curie temperature of the NKN-LST-ZnO ceramics slightly decreased with adding ZnO. The dielectric constant, piezoelectric constant ($d_{33}$) and electromechanical coupling factor ($k_p$) increased at the small amount of ZnO addition, which might be due to the increase in density. The high piezoelectric properties = 153 pC/N, electromechanical coupling factor = 0.484 and dielectric constant = 2883 were obtained for the NKN-LST+0.5ZnO ceramics sintered at $1050^{\circ}C$ for 2h.

The Structure and Electrical Characteristics of ZnO Varistors Surface using-Fractal (프랙탈을 이용한 ZnO 바리스터 표면 구조 및 전기적 특성)

  • Oh, Soo-Hong;Hong, Kyung-Jin;Lee, Jin;Lee, Joon-Ung;Kim, Tae-Sung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.10
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    • pp.834-839
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    • 2000
  • The structural properties that SEM photograph of ZnO varistors surface studied by fractal mathematics program were investigated to verify the relations of electrical characteristics. The SEM photograph of ZnO varistors surface were changed by binary code and the grain shape of that were analyzed by fractal dimension. The void of ZnO varistors surface was found by fractal program. The relation between grain density and electrical properties depend on fractal dimension. The grain size in ZnO varistors surface was decreased by increasing of Sb$_2$O$_3$ addition. The spinel structure was formed by Sb$_2$O$_3$addition and it was depressed the ZnO grain formation. The grain size of ZnO by Sb$_2$O$_3$addition were from 5 to 10[${\mu}{\textrm}{m}$]. Among of ZnO varistors, fractal dimension of ZnO4 was very high as a 1.764. The density of grain boundary in ZnO2 and ZnO3 varistors surface was 15[%] by formed spinal structure. The breakdown electric field of ZnO2 that fractal dimension has 1.752 was very high to be 8.5[kV/cm]. When the fractal dimensin was high, the grain shape of ZnO varistors was complex and the serial layers of ZnO grain was increased.

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Electrical Properties of Zinc Oxide Varistor with $\alpha-Zn_7Sb_2O_{12}$ ($\alpha-Zn_7Sb_2O_{12}$ 첨가에 의한 Zinc Oxide 바리스터의 전기적 특성)

  • 김경남;한상목
    • Journal of the Korean Ceramic Society
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    • v.31 no.11
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    • pp.1396-1400
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    • 1994
  • Electrical properties in the ZnO-Bi2O3-CoO-Zn7Sb2O12 system were investigated with Zn7Sb2O12 content (0.1~2 mol%). The increase of the Zn7Sb2O12 content inhibited the grain growth of ZnO, which showed a narrow grain size distribution of ZnO. The breakdown voltage (Vb) increased markedly with 1 mol% Zn7Sb2O12 addition due to the grain growth control behaviour of the Zn7Sb2O12 . The nonlinear I-V characteristic was significantly influenced by the Zn7Sb2O12 content (or Bi2O3/Zn7Sb2O12 ratio). Addition of 0.5 mol% Zn7Sb2O12 showed the highest nonlinear coefficient ($\alpha$) of 43. The leakage current in prebreakdown region was decreased with increasing Zn7Sb2O12 content.

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The Microwave Dielectric Properties of $ZnNb_2O_{6}$ Ceramics with Sintering Temperature and CuO Addition (소결온도와 CuO 첨가에 따른 $ZnNb_2O_{6}$ 세라믹스의 마이크로파 유전특성)

  • 김정훈;김지헌;배선기;이성갑;이영희
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.7
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    • pp.347-351
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    • 2004
  • The $ZnNb_2O_{6}$ ceramics with CuO(1, 3, 5wt%) were prepared by the conventional mixed oxide method. The ceramics were sintered at the temperature of $950^{\circ}C$$1075^{\circ}C$ for 3hr in air The structural properties and the microwave dielectric properties of $ZnNb_2O_{6}$ ceramics were investigated with sintering temperature and the addition of CuO. Increasing the addition of CuO, the peak of second phase($Cu_3Nb_2O_{8}$) was increased. The grain size of the $ZnNb_2O_{6}$ ceramics with CuO was increased with CuO addition at same temperature. The dielectric constant of $ZnNb_2O_{6}$ ceramics with CuO was increased with sintering temperature and CuO addition. While the quality factor of the $ZnNb_2O_{6}$ ceramics with lwt% CuO depended on sinterability, the quality factor of $ZnNb_2O_{6}$ with 3wt% and 5wt% CuO depended on second Phase due to the CuO addition. The optimum dielectric Properties of $\varepsilon$$_{r}$ = 21.73 Q${\times}$f = 19,276 were obtained from the condition of 3wt% CuO addition and sintering temperature of $1025^{\circ}C$(3hr).

Piezoelectric properties of Pb-free BNKT ceramics with ZnO addition (ZnO첨가에 따른 무연 BNKT계 세라믹스의 압전특성)

  • Ryu, Sung-Lim;Kim, Ju-Hyun;Lee, Mi-Young;Yoo, Ju-Hyun;Seo, Sang-Hyun;Chung, Kwang-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.193-195
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    • 2005
  • [ $0.96[Bi_{0.5}(Na_{0.84}K_{0.16})_{0.5}TiO_3]+0.04SrTiO_3+0.3wt%Nb_2O_5+0.2wt%La_2O_3+xwt%ZnO$ ], were studied in order to develope the superior piezoelectric properties of Lead-free piezoelectric ceramics. With increasing amount of ZnO addition, density showed the maximum value of 5.79(g/$cm^3$) at 0wt% ZnO addition, and electromechanical coupling factor($k_p$) and dielectric constant decreased, and mechanical quality factor($Q_m$) increased and showed the maximum value of 280 at 0.4wt% ZnO addition.

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The effect of Zn2TiO4 on willemite crystalline glaze (Zn2TiO4가 아연결정유약에 미치는 효과)

  • Lee, Chi-Youn;Lee, Hyun-Soo;Shin, Kyung-Hyun
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.24 no.2
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    • pp.70-76
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    • 2014
  • $Zn_2TiO_4$, using an anatase form of $TiO_2$ on zinc crystalline glaze, was shown as effective nuclear agent. Thus the effects on glaze were studied with synthesized $Zn_2TiO_4$ at low temperature. First, the chromophore elements were employed in synthesized $Zn_2TiO_4$ then add them in the zinc crystalline glaze. Crystal creation and development of color by $Zn_2TiO_4$ addition on the zinc crystalline glaze were more effective. Addition of $Zn_2TiO_4$, which is developed in low range temperature, is effected as zinc crystalline nuclear in the willemite glaze. When 5 wt% of synthesized $Zn_2TiO_4$ was added to the willemite glaze, nuclear creation increases and steadily retains. Therefore addition of respectively doped $Zn_2TiO_4$ with CoO, NiO, and CuO would increase doped effects in the glaze, various color willemite crystal were obtained.

Enhanced Stability of Organic Photovoltaics by Additional ZnO Layers on Rippled ZnO Electron-collecting Layer using Atomic Layer Deposition

  • Kim, Kwang-Dae;Lim, Dong Chan;Jeong, Myung-Geun;Seo, Hyun Ook;Seo, Bo Yeol;Lee, Joo Yul;Song, Youngsup;Cho, Shinuk;Lim, Jae-Hong;Kim, Young Dok
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.353-356
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    • 2014
  • We fabricated organic photovoltaic (OPV) based on ZnO ripple structure on indium tin oxide as electron-collecting layers and PTB7-F20 as donor polymer. In addition, atomic layer deposition (ALD) was used for preparing additional ZnO layers on rippled ZnO. Addition of 2 nm-thick ALD-ZnO resulted in enhanced initial OPV performance and stability. Based on photoluminescence results, we suggest that ALD-ZnO layers reduced number of surface defect sites on ZnO, which can act as electron-hole recombination center of OPV, and increased resistance of ZnO towards surface defect formation.

Effects of ZnO and PbO on the Magnetic Properties of Sr-ferrite (ZnO와 PbO가 Sr-페라이트의 자기적 특성에 미치는 영향)

  • 김정훈;김동엽;김동진;정완배;오재현
    • Journal of the Korean Ceramic Society
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    • v.28 no.6
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    • pp.471-477
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    • 1991
  • Effects of ZnO, PbO and SiO2 on the grain growth and magnetic properties of Sr-ferrite were investigated. (1) Addition of ZnO to Sr-ferrite increased remanence, but decreased coercivity and maximum energy product. (2) Addition of PbO up to 0.5 wt% increased (B$.$H)max of Sr-ferrite, but addition more than 0.5 wt% decreased (B$.$H)mzx (3) SiO2 addition to the 0.5 wt% PbO doped Sr-ferrite decreased remanence and increased coercivity. The coercivity increase in due to the grain refinement effect of SiO2. But addition of SiO2 more than 0.5 wt% invoked a decrease of coercivity and (B$.$H)max of Sr-ferrite due to abnormal grain growth. Sr-ferrite magnet having maximum energy product of 3.7MGOe was fabricated by using the roasting product of Pyrrhotite.

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