• Nano
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• v.13 no.12
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• pp.1850149.1-1850149.10
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• 2018

Ferroelectric particles have been applied in the photocatalytic field because the spontaneous polarization results in the internal electric field, which can accelerate the separation and migration of photogenerated carriers. In this study, the $BaTiO_3$ (BT) fibers are synthesized by electrospinning. The BT fibers calcined above $800^{\circ}C$ exhibit a strong ferroelectric property, which is verified by a typical butterfly-shaped displacement-voltage loop. It is found that the BT fibers with the single-domain structure exhibit better photocatalytic performance than that with the multi-domain configuration. When the single-domain transforms into multi-domain, the integrated internal electric field correspondingly breaks up, inducing that the internal electric field might cancel each other out and diminish the separation of photogenerated carriers. Also, the Au nanoparticles can improve the photocatalytic activity further on account of the surface plasmon resonance. Therefore, it is suggested that Au nanoparticles decorated on ferroelectric BT nanomaterials are promising photocatalysts.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.462-464
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• 1990

We report the development of a surface discharge preionized KrF discharge Laser with a new type of high-brightness Corona preionizer using a segmented columnar $BaTiO_3$ dielectric. This Laser characteristic was higher value than that obtained with the conventional corona preionizer using a glass, $Al_2O_3ceramic$, Kapton film, or a Teflon insulator.

• 한국초전도학회:학술대회논문집
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• v.15
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• pp.48-48
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• 2005

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.103.2-103.2
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• 2008

• Journal of the Microelectronics and Packaging Society
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• v.3 no.1
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• pp.33-40
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• 1996

MOD법에 의해 BST박막을 제조하고 전기적 특성을 측정함으로써 마이크로 회로에 적용가능성을 타진하였다. MOD 공정의 선구물질로서 barium neodecanoate, strontium 2-ethylhexanoate 및 titanium dimethoxy 야-2-ethylheanoate를 합성하였다, 합성된 선구물 질들을 Ba0.5Sr0.5TiO3가 되도록 화학양론적으로 혼합하여 공통용매인 p-xylene에 녹인다음 기판위에 spin coating 방법으로 박막을 형성하여 건조하고 소성하였다. 사용된 기판은 ITO/glass, Pt/SiO2/Si, Pt/Ti/SiO2/Si 및 Pt foil을 사용하였다. 소성 속도를 빨리했을 경우 소성속도를 느리게 했을때에 비하여 훨씬 균일하고 치밀한 박막을 얻을수 있었다, 여러 가 지 제조조건의 변화에 따른 유전상수 I-V 특성 및 C-V 측성 등의 전기적 특성을 측정하고 고찰하였다.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1254-1256
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• 1994

0.15$(Ba_{0.95}Sr_{0.05})$O-0.15$(Sm_{2(1-x)}Nd-{2x})O_3-0.7TiO_2 (x=0{\sim}10[m/o])$ ceramics were fabricated by mixed-oxide method. Microwave dielectric properties was investigated with the contents of $Nd_2O_3$. Increasing the contents of $Nd_2O_3$ from 0 to 6[m/o], sintered density was increased 5.53 to $5.68[g/ cm^3]$. In the specimen with contents of $Nd_2O_3$(6[m/o]), dielectric content was maximum value of 78.14 and decreased with increasing the contents of $Nd_2O_3$. Quality factor was increased with the contents of $Nd_2O_3$.

• Journal of the Korean Ceramic Society
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• v.53 no.2
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• pp.145-149
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• 2016

$(Bi_{1/2}Na_{1/2})_{0.94}Ba_{0.06}(Ti_{1-x}Nb_x)O_3$ (BNBTxNb) ceramics were investigated in terms of the crystal structure as well as the ferroelectric, dielectric, and piezoelectric properties. While little change was observed in the microstructure except for a slight decrease in the average grain size, a significant change was noticed in the temperature dependence of dielectric and piezoelectric properties. It was shown that the property changes are closely related to the downward shift in the position of the ferroelectric-to-relaxor transition temperature with increasing amount of Nb doping. A special emphasis is put on the fact that Nb doping is so effective at decreasing the ferroelectric-to-relaxor transition temperature that even at no more than 2 at.% Nb addition, the transition temperature was already brought down slightly below room temperature, resulting in the birth of a large strain at 0.46 %, equivalent to $S_{max}/E_{max}=767pm/V$.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.408.2-409
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• 2016

Theoretically, the dye-sensitized solar cells (DSSCs) are high efficiency solar cells. However DSSCs have low power conversion efficiency (PCE) than silicon based solar cells. In this study, we use the phosphor materials, such as $Y_2O_3:Eu$ (Red), $Zn_2SiO_4:Mn$ (Green), $BaMgAl_{14}O_{23}:Eu$ (Blue), to enhance the PCE of DSSCs. Three phosphors were prepared and used as an effective scattering layer on the transparent $TiO_2$ with doctor blade method. We confirmed that the three scattering layers improve the PCE and Jsc due to the light harvesting enhancement via increased the scattering and absorbance in visible range. Under the sun illumination AM 1.5 conditions, the PCE of the mesoporous $TiO_2$ based DSSCs is 5.18 %. The PCE of the DSSCs with Y2O3:Eu, $Zn_2SiO_4:Mn$ and $BaMgAl_{14}O_{23}:Eu$ as scattering layer were enhanced to 5.66 %, 5.72% and 5.82%, respectably. In order to compare the optical properties change, DSSCs were measured by EQE, reflectance and PCE. At the same time, FE-SEM and XRD were used to confirm the structural changes of each layer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.866-869
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• 2001

In this study, (Ba,Sr)TiO$_3$(BST) thin films were etched with a magnetically enhanced inductively coupled plasma(MEICP). Etching characteristics of BST thin films including etch rate and selectivity were evaluated as a function of the etching parameters such as gas mixing ratio, rf power, dc bias voltage and chamber pressure. The maximum etch rate of the BST films was 1700 $\AA$/min at Ar(90)/CF$_4$(10), 600 W/350 V and 5 mTorr. The selectivity of BST to PR was 0.6, 0.7, respectively. To analyze the composition of surface residue remaining after the etching, samples etched with different CF$_4$/Ar gas mixing ratio were investigated with X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). From the results of XPS and SIMS, there are chemical reaction between Ba, Sr, Ti and C, F radicals during the etching and remained on the surface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05b
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• pp.107-110
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• 2002

The optical memory devices of BST thin films to composite $(Ba_{0.7}\;Sr_{0.3})TiO_{3}$ using sol-gel method were fabricated by changing of the depositing layer number on $Pt/Ti/SiO_{2}/Si$ substrate. The structural properties of optical memory devices to be ferroelectric was investigated by fractal analysis and 3-dimension image processing. The thickness of BST thin films at each coating numbers 3, 4 and 5 times was $2500[\AA]$, $3500[\AA]$ and $3800[\AA]$. BST thin films exhibited the most pronounced grain growth. The surface morphology image was roughness with coating numbers. The thin films increasing with coating numbers shows a more textured and complex configuration.