• Bulletin of the Korean Chemical Society
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• 제24권3호
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• pp.311-317
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• 2003

Vanadium oxides supported on zirconia and modified with MoO₃were prepared by adding Zr(OH)₄powder into a mixed aqueous solution of ammonium metavanadate and ammonium molybdate followed by drying and calcining at high temperatures. The characterization of prepared catalysts was performed using FTIR, Raman spectroscopy and solid-state $^{51}V$ NMR. In the case of a calcination temperature of 773 K, for samples containing low loading of $V_2O_5$, below 15 wt %, vanadium oxide was in a highly dispersed state, while for samples containing high loading of $V_2O_5$, equal to or above 15 wt %, vanadium oxide was well crystallized because the $V_2O_5$ loading exceeded the formation of a monolayer on the surface of $ZrO_2$. The $ZrV_2O_7$ compound was formed through the reaction of $V_2O_5\;and\;ZrO_2$ at 873 K and the compound decomposed into $V_2O_5\;and\;ZrO_2$ at 1073 K, which were confirmed by FTIR spectroscopy and solid-state $^{51}V$ NMR. IR spectroscopic studies of ammonia adsorbed on $V_2O_5-MoO_3/ZrO_2$ showed the presence of both Lewis and Bronsted acids.

• 한국세라믹학회지
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• 제25권4호
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• pp.335-340
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• 1988

The change in microstructure and the electrical properties of Pb(In1/2Nb1/2)O3-PbTiO3 Ceramics caused by V2O5 addition were studied. The results are ; 1. interability was increased because the mass transport through the second phase formed by V2O5 addition increased. 2. ith addition of V2O5, tetragonality and Curie temperature increased. The maximum value of kp was observed when 0.5wt% of V2O5 was added. 3. he second phase formed by V2O5 accelerated the grain growth, and existed in grain boundary. Electrical properties were changed by corelations between tetragonality and the amount of second phase.

• 한국전기전자재료학회논문지
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• 제14권6호
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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.

• 공업화학
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• 제10권3호
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• pp.382-387
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• 1999

졸-겔법을 이용하여 무정형의 $V_2O_5$ 겔을 제조한 후, 스핀코우팅에 의하여 균일한 박막의 $V_2O_5$, xerogel 전극을 개발하여 전극의 임피던스 특성을 연구하였다. $V_2O_5$겔이 xerogel로 전환되는 과정에서 스핀코우팅 방법이 $V_2O_5$의 비등방성을 감소시킬 뿐만 아니라 우수한 전기화학적 특성을 갖게 하였다. $V_2O_5$ xerogel의 리튜이온 확산계수 및 전하이동저항은 xerogel내에 존재하는 리튬이온의 물분율이 변함에 따라 증감하였으며 가역성이 우수하였다.

• 대한화학회지
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• 제61권1호
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• pp.12-15
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• 2017

We presented a mapping the work function of the vanadium pentoxide ($V_2O_5$) nanonet structures by scanning Kelvin probe microscopy (SKPM). In this measurement, the $V_2O_5$ nanonet was self-assembled via dropping the solution of $V_2O_5$ nanowires (NWs) onto the $SiO_2$ substrate and drying the solvent, resulting in the networks of $V_2O_5$ NWs. We found that the SKPM signal as a surface potential of $V_2O_5$ nanonet is attributed to the contact potential difference (CPD) between the work functions of the metal tip and the $V_2O_5$ nanonet. We generated the histograms of the CPD signals obtained from the SKPM mapping of the $V_2O_5$ nanonet as well as the highly ordered pyrolytic graphite (HOPG) which is used as a reference for the calibration of the SKPM tip. By using the histogram peaks of the CPD signals, we successfully estimated the work function of ~5.1 eV for the $V_2O_5$ nanonet structures. This work provides a possibility of a nanometer-scale imaging of the work function of the various nanostructures and helps to understand the electrical characteristics of the future electronic devices.

• E2M - 전기 전자와 첨단 소재
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• 제6권2호
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• pp.129-136
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• 1993

습도 감지소자의 물질 중 이온형의 대표적인 물질인 TiO$_{2}$ 습도 센서와 TiO$_{2}$에 V$_{2}$O$_{5}$를 첨가한 TiO$_{2}$-V$_{2}$O$_{5}$ 세라믹 습도센서를 제작하고 V$_{2}$O$_{5}$함량의 변화, 열처리 온도 및 열처리 시간에 따른 습도감지 특성 및 동작온도에 따른 특성 등을 조사하였으며 XRD와 SEM으로 그 원인을 규명하였다. TiO$_{2}$에 V$_{2}$O$_{5}$를 첨가하면 선형성이 좋아지는 것을 알 수 있었고 제작한 시료 중 V$_{2}$O$_{5}$의 함량이 1mol% 열처리 조건이 1000.deg.C, 1시간인 소자는 동작온도 40.deg.C에서 약 95%의 감도를 나타내었다.

• 공업화학
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• 제16권4호
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• pp.491-495
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• 2005

Al이 0.01에서 0.05 몰 도핑된 오산화바나듐을 졸-겔법을 이용하여 제조하였고, Al이 도핑된 오산화바나듐의 화학적성질과 전기화학적 특성을 조사하기 위하여 $Li/Al_xV_2O_5$ 전지를 만들었다. $Al_xV_2O_5$ xerogel의 표면형상은 비등방성의 주름진 판상을 이루며 층간거리는 약 $11.5{\AA}$이었다. IR 스펙트럼에 의하면 도핑된 Al이 $V_2O_5$의 vanadyl기에 결합하고 있는 것으로 나타났다. $Al_xV_2O_5$ xerogel은 가역성과 에너지밀도가 $V_2O_5$보다 향상되었다. 또한 10 mA/g의 방전율로 얻은 $Al_{0.05}V_2O_5$ xerogel의 비용량은 200 mAh/g 이상이었으며, 1.9 V에서 3.9 V 전위영역에서 31회의 연속 충방전 실험을 한 결과 약 90%의 사이클효율을 나타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 학술대회 논문집 전문대학교육위원
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• pp.138-140
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• 2007

$TiO_2-V_2O_5$ sol was fabricated using sol-gel method and $TiO_2-V_2O_5$ thin films were fabricated using dip-coating method. $V_2O_5$ sol was added 0.01mo1e, 0.03mo1e, 0.05mo1e into $TiO_2$ sol. Viscosity of sol increased fast from about 1,000 minutes and sol began gelation from about 10,000 minutes. As a results of crystalline properties, $V_2O_5$ peaks were not found despite of $V_2O_5$ addition. Endothermic reaction occurred due to evaporation of solvent and dissociation of OH at $80^{\circ}C$. Exothermic reaction occurred due to combustion and oxidation of solvent at $230^{\circ}C$, occurred to combustion and oxidation of alkyl group at $350^{\circ}C$. Thickness of thin films increased $0.1{\sim}0.25{\mu}m$ every a dipping.