• Title/Summary/Keyword: $CuO-P_2O_5-V_2O_5$

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Crystallization and Electrical Conductivity of $CuO-P_{2}O_{5}-V_{2}O_{5}$ Glass for Solid-state Electrolyte (고체전해질용 $CuO-P_{2}O_{5}-V_{2}O_{5}$유리의 결정화와 전기전도도)

  • 손명모;이헌수;구할본
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.1018-1021
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    • 2001
  • 1018-1021 The CuO-P$_2$O$_{5}$ containing P$_2$O$_{5}$ as glass-former were prepared by press-quenching method on the copper plate. By post-heat treatment of these glasses, the CuO-P$_2$O$_{5}$ -V$_2$O$_{5}$ -g1ass ceramics was obtained and the crystallization behavior and dc conductivities were investigovted. The heat-treated glass-ceramics decreased in electrical conductivity by the order of 10$^1$ compared to amorphous glass. The linear relationship between In($\sigma$T) and T$^{-1}$ indicated that electrical conduction in CuO-P$_2$O$_{5}$ -V$_2$O$_{5}$ -gass occurred by a small polaron hopping.

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Crystallization and Conductivity of $CuO-P_{2}O_{5}-Nb_{2}O_{5}-V_{2}O_{5}$ Glasses ($CuO-P_{2}O_{5}-Nb_{2}O_{5}-V_{2}O_{5}$ 유리의 결정화와 전기전도도)

  • 손명모;이헌수;구할본
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.291-294
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    • 2000
  • The crystallization behavior and dc Conductivities of CuO-P$_2$O$_{5}$ -Nb$_2$O$_{5}$ -V$_2$O$_{5}$ glasses prepared by quenching on the copper plate were investigated. The conductivities of the glasses were range from 10$^{-5}$ s.$cm^{-1}$ / at room temperature, but the conductivities of the glass-ceramics were 10$^{-3}$ s.$cm^{-1}$ / increased by 10$^2$order. The crystalline product in the glass-ceramics was CuV$_2$O$_{6}$ . The linear relationship between in($\sigma$T) and T$^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping mechanism.

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Crystallization and conductivity of CuO--$P_{2}O_{5}$-$Nb_{2}O_{5}$-$V_{2}O_{5}$Glasses for Solid State Eletrolyte (고체전해질용 CuO-$P_{2}O_{5}$-$Nb_{2}O_{5}$-$V_{2}O_{5}$계 유리의 결정화와 전기전도도)

  • 손명모;이헌수;김종욱;김윤선;구할본
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.14 no.6
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    • pp.475-480
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    • 2001
  • Glasses in he system CuO-P$_2$O$_{5}$ -Nb$_2$O$_{5}$ -Nb$_2$O$_{5}$ -V$_2$O$_{5}$ were prepared by a press-quenching method on the copper plate. the glass-ceramics from these glasses were obtained by post-heat treatment, and the crystallization behavior and DC conductivities were determined. The conductivities of the glasses were range from 10$^{-6}$ s.$cm^{-1}$ / at room temperature ,but the conductivities of the glass-ceramics were 10$^{-3}$ s.$cm^{-1}$ / increased by 10$^3$ order. The crystalline product in the glass-ceramics was CuV$_2$O$_{6}$ . the crystal growth of CuV$_2$O$_{6}$ phase increased with heat-treatment conditions. The linear relationship between il($\sigma$T) and T$^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping(SPH) mechanism.

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Crystallization and Electrical properties of $CuO-P_2O_5-V_2O_5$ Glass for solid state Electrolyte (고체 전해질용 $CuO-P_2O_5-V_2O_5$ 유리의 결정화와 전기 전도도)

  • Son, Myung-Mo;Lee, Heon-Soo;Chun, Yon-Soo;Gu, Hal-Bon;Lee, Sang-Geun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.934-937
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    • 2003
  • Glasses in the system $CuO-P_2O_5-V_2O_5$ were prepared by a press-quenching method on the copper plate. The glass-ceramics from these glasses were obtained by post-heat treatment, and the crystallization behavior and DC conductivities were determined. The conductivities of the glasses were range from $10^{-6}s.Cm^{-1}$ at room temperature, but the conductivities of the glass-ceramics were $10^{-3}s.Cm^{-1}$ increased by $10^3$ order. The crystalline product in the glass-ceramics was $CuV_2O_6$. Heat-treatment conditions influenced the crystal growth of $CuV_2O_6$ and conductivity. The linear relationship between in (${\sigma}T$) and $T^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping(SPH) mechanism.

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Photoelectrochemical Water Splitting on a Delafossite CuGaO2 Semiconductor Electrode

  • Lee, Myeongsoon;Kim, Don;Yoon, Yong Tae;Kim, Yeong Il
    • Bulletin of the Korean Chemical Society
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    • v.35 no.11
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    • pp.3261-3266
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    • 2014
  • A pellet of polycrystalline $CuGaO_2$ with a delafossite structure was prepared from $Ga_2O_3$ and CuO by high-temperature solid-state synthesis. The $CuGaO_2$ pellet was a p-type semiconductor for which the electrical conductivity, carrier density, carrier mobility and Seebeck coefficient were $5.34{\times}10^{-2}{\Omega}^{-1}cm^{-1}$, $3.5{\times}10^{20}cm^{-3}$, $9.5{\times}10^{-4}cm^2V^{-1}s^{-1}$ at room temperature, and $+360{\mu}V/K$, respectively. It also exhibited two optical transitions at about 2.7 and 3.6 eV. The photoelectrochemical properties of the $CuGaO_2$ pellet electrode were investigated in aqueous electrolyte solutions. The flat-band potential of this electrode, determined using a Mott-Schottky plot, was +0.18 V vs SCE at pH 4.8 and followed the Nernst equation with respect to pH. Under UV light illumination, a cathodic photocurrent developed, and molecular hydrogen simultaneously evolved on the surface of the electrode due to the direct reduction of water without deposition of any metal catalyst.

Self-Assembly of Vanadium Borophosphate Cluster Anions: Synthesis and Structures of (NH4)(C2H10N2)5.5[Cu(C2H8N2)2]3[V2P2BO12]6·17H2O and (NH4)(C2H10N2)3.5[Cu(C2H8N2)2]5[V2P2BO12]6·18H2O

  • Jung, Kyung-Na;Cho, Yoon-Suk;Yun, Ho-Seop;Do, Jung-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.26 no.8
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    • pp.1185-1189
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    • 2005
  • Two new copper vanadium borophosphate compounds, $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O,\;Cu-VBPO1\;and\;(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, Cu-VBPO2 have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, thermogravimetric analysis, IR spectroscopy, and elemental analysis. The structure of Cu-VBPO1 contains a layer anion, {$[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6$}$^{12-}$, whereas Cu-VBPO2 has an open framework anion, {$[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6$}$^{8-}$. Crystal Data: $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O$, monoclinic, space group I2/m (no. 12), $\alpha$ = 15.809(1) $\AA$, b = 31.107(2) $\AA$, c = 12.9343(8) $\AA$, $\beta$ = 104.325(1)$^{\circ}$, Z = 2; $(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, tetragonal, space group $P4_2$/mnm (no.136), $\alpha$ = 26.832(1) $\AA$, c = 18.021(1) $\AA$, Z = 4.

UV/O3 Process Time Effect on Electrical Characteristics of Sol-gel Processed CuO Thin Film Transistor (UV/O3 조사 시간에 따른 Sol-gel 공정 기반 CuO 박막 트랜지스터의 전기적 특성 변화)

  • Lee, Sojeong;Jang, Bongho;Kim, Taegyun;Lee, Won-Yong;Jang, Jaewon
    • Journal of IKEEE
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    • v.22 no.1
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    • pp.1-5
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    • 2018
  • In this research, sol-gel processed CuO p-type thin film transistors were fabricated with copper (II) acetate monohydrate precursors. After $500^{\circ}C$ annealing process, the deposited thin films were fully converted into CuO. We investigated $UV/O_3$ process time effect on electrical characteristics of sol-gel processed CuO thin film transistors. After 600 sec $UV/O_3$ process, the fabricated CuO thin film transistor delivered field effect mobility in saturation regime of $5{\times}10^{-3}\;cm^2/V{\cdot}s$ and on/off current ratio of ${\sim}10^2$.

Low Temperature Sintering of (Bi1/2Na1/2)TiO3-SrTiO3 Ceramics and Their Ferroelectric and Piezoelectric Properties (BNT-ST 세라믹스의 저온 소결과 강유전 및 압전 특성)

  • Hyunhee Kwon;Ga Hui Hwang;Chae Il Cheon;Ki-Woong Chae
    • Journal of Sensor Science and Technology
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    • v.32 no.4
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    • pp.238-245
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    • 2023
  • 0.75(Bi1/2Na1/2)TiO3-0.25SrTiO3 (BNT-25ST) ceramics with high densities were successfully prepared at a sintering temperature of 1,000℃ by adding a mixture of 1 mol% CuO and 0.5 mol% Na2CO3 or 0.5 mol% CuO and 0.25 mol% Na2CO3. Double polarization-electric field (P-E) hysteresis curves and sprout-shaped bipolar strain-electric field (S-E) hysteresis curves with small negative strains were observed in the pristine and CuO-added BNT-25ST ceramics whereas the Na2CO3-added sample showed similar P-E and S-E curves to a typical ferroelectric. The pristine BNT-25ST ceramics showed an extremely large strain and a large-signal piezoelectric strain constant (d33*): 0.287 % at 80 kV/cm and 850 pm/V at 20 kV/cm. Similar values, 0.248 % at 80 kV/cm and 655 pm/V at 20 kV/cm, were obtained in the CuO-added sample. However, the pristine and CuO-added samples showed large hysteresis in unipolar S-E curves at an electric field of less than 20 kV/cm. The Na2CO3-added sample showed smaller values of the strain and d33* but displayed a linear change and small hysteresis in the unipolar S-E curve. The co-added sample with CuO and Na2CO3 displayed intermediate P-E and S-E hysteresis curves.

Geochemical Dispersion and Enrichment of Fluvial Sediments Depending on the Particla Size Distribution (입도분포에 따른 하상퇴적물의 지구화학적 분산 및 부화)

  • 이현구
    • Economic and Environmental Geology
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    • v.32 no.3
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    • pp.247-260
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    • 1999
  • Geochermical characteristics of the fluvial sediments deprnding on particle size distribution size were investigated in the respect of majir, minor and rare eath element chemisitry. Ratios of $Al_{2}O_{3}/Na_{2}O$ and $K_{2}O/Na_{2}O$ of the sediments show the homogeneous valus, and partly positive correlation with $SiO_{2}/Al_{2}O_{3}$, respecively. Characteristics of minor element ratios (V/Ni, Cr/V, Ni/Co and Zr/Hf)are within the lower and narrow range. Thesesuggested that sediment sources may be acidic to intermediate granitic rock, and may be explained by simple weathering and sedimentation. With increasing SiO2 contents, concentrations of $Al_{2}O_{3}$, $Fe_{2}O_{3}$, CaO and MgO decreased, but those of $K_{2}O$ and $Na_{2}O$ increased, Concentrations of Ba, Be, Cs, Cu, Li, Ni, Sr, V and Zr show comparatively normal negative and some positive trends. Compared with the mean composition of granite, concentrations of $Al_{2}O_{3}$, $Fe_{2}O_{3}$, MnO, CaO and MgO in the sediments of the study area were highly enriced. Among some minor and rare earth elements, concentrations of As, Cd, Cu, and V were enriched, but those of Be, Ce, Rb, Sc, Sr and Zn were depleted when compared with average composition of granite. By decreasing of particle size fractions, SiO2, Rb and Sr conterts decreased, but concentrations of $Al_{2}O_{3}$, $Fe_{2}O_{3}$, CaO, MgO, $TiO_{2}$, MgO, $P_{2}O_{5}$, Be, Cu, Hf, Pb, V and Zr increased. From the correlations between particle size fractions and element concenreations, some elements of $Fe_{2}O_{3}$, CaO, MgO, $P_{2}O_{5}$, Cu, Ni, Zn and Zr showed typical trends in the secondary contramination sediments. These trends are typically shown under 100 mesh fractions. It indicates that the fraction of minus 100 mesh is the optimum size fraction for geochemical and environmental survey.

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Studies on the Paramagnetic Impurity $Y_2BaCuO_5$ in Superconducting $YBa_2Cu_3O_{7-\delta}$ Phase

  • Choy Jin-Ho;Chun Sung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.10 no.1
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    • pp.5-8
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    • 1989
  • Conventional ceramic method has been used to prepare the green phase, $Y_2BaCuO_5$, commonly observed in 90-K superconductor $YBa_2Cu_3O_P{7-{\delta}}$as an impurity phase. The powder X-ray diffraction analysis indicates that $Y_2BaCuO_5$ has an orthorhombic symmetry with lattice parameter of a = 12.2 $\AA$, b = 5.61 $\AA$, and c = 7.14 $\AA.$ The average g-value 2.13 observed in ESR spectrum is attributable to Cu2+ stabilized in $C_{4v}$ field. From the magnetic susceptibility ($\mu$eff = 2.29 BM) and the ESR measurements, it is confirmed that Cu(II) $3d^9$ electrons in $Y_2BaCuO_5$ are localized and can be characterized by Curie-Weiss behavior. Optical reflectance spectrum shows a broad absorption peak around 680 nm due to dxy ${\rightarrow}$ $dx^2-y^2$ eletronic transition.