• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2161-2168
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• 2008

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.284-285
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• 2003

Significant research interest in the growth and characterization of $Y_2$O$_3$：Eu$^{3+}$ thin films has been shown over the last few years because of the promise for applications of display devices. Although an Eu-doped oxysulfide (Eu： $Y_2$O$_2$S) which has an efficiency of 13％ has been used for a traditional cathode ray tube (CRT) red phosphor, the sulfide system is known to degrade rapidly under the high current densities needed for field-emission display (FED) technology. (omitted)d)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.157-159
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• 2005

본 연구에서는 저온 액상반응법을 이용하여 활성제 Eu의 농도를 10wt%로 도핑하고 열처리를 각각 450, 700, $900^{\circ}C$로 1h 유지하여 $Gd_2O_3:Eu^{3+}$ 나노형광체를 합성하였다. 제조된 형광체의 결정화, 입자크기를 XRD, BET로 분석하였고, 이들이 발광 휘도에 미치는 영향을 확인하였다. 또한 합성된 형광체의 PL(photoluminescence) 특성을 알아보기 위해 여기파장 254nm 의한 발광스펙트럼, 611nm에 의한 여기스펙트럼을 조사하였다. 발광 특성은 611nm에서 주 peak을 갖는 $Eu^{3+}$ 이온에 의한 $^5D_0-^7F_{J(J=0,1,2)}$ 전이에 기인된 전형적인 Red 형광체의 특성을 나타냈고, 입자크기는 평균 20-60nm 정도이고, 발광강도는 열처리 온도가 증가함에 따라 향상되었다.

• Journal of the Korean Ceramic Society
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• v.51 no.6
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• pp.605-611
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• 2014

$SrGd_{2-x}(MoO_4)_4:Er^{3+}/Yb^3$ phosphors with doping concentrations of $Er^{3+}$+ and $Yb^{3+}$ ($x=Er^{3+}+Yb^{3+}$, $Er^{3+}=0.05$, 0.1, 0.2, and $Yb^{3+}=0.2$, 0.45) were successfully synthesized by the cyclic microwave-modified sol-gel method, and their upconversion mechanism and spectroscopic properties have been investigated in detail. Well-crystallized particles showed a fine and homogeneous morphology with grain sizes of $2-5{\mu}m$. Under excitation at 980 nm, $SrGd_{1.7}(MoO_4)_4:Er_{0.1}Yb_{0.2}$ and $SrGd_{1.5}(MoO_4)_4:Er_{0.05}Yb_{0.45}$ particles exhibited a strong 525-nm emission band, a weak 550-nm emission band in the green region, and a very weak 655-nm emission band in the red region. The Raman spectra of the doped particles indicated the domination of strong peaks at higher frequencies of 1023, 1092, and $1325cm^{-1}$ and at lower frequencies of 223, 2932, 365, 428, 538, and $594cm^{-1}$ induced by the incorporation of the $Er^{3+}$+ and $Yb^{3+}$+ elements into the $Gd^{3+}$ site in the crystal lattice, which resulted in the unit cell shrinkage accompanying a new phase formation of the $[MoO_4]^{2-}$ groups.

• Journal of the Korean institute of surface engineering
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• v.32 no.6
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• pp.665-670
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• 1999

PDP용 적색형광체는 penning가스(Ne 및 5% Xe혼합가스)에 의해 방출되는 147nm파장에서 쉽게 여기되어 논은 양자효율을 주는 물질로 이루어지는데 본 실험은 발광효율을 높이기 위하여 $Y_2$$O_3$:Eu, $(Y,Gd)_2$$O_3$:Eu 및 $(Y,Cd)BO_3$:Eu를 공침법으로 합성하여 부활제인 $Bu^{3+}$ /의 농도, Flux첨가에 따른 미시조직의 변화등을 여기 방출 스펙트럼을 통해 발광효율을 조사하여 다음과 같은 결론을 얻었다. $Y_2$$O_3$:Eu 형광체 합성시 최적조정은 $Y_2$$O_3$에 대한 $Eu_2$$O_3$의 몰비는 5:1, $BaCO_3$ 첨가시 몰비는 15:1로 나타났으며 2차 소성시 $1200^{\circ}C$이상에서 1~3$\mu\textrm{m}$의 구형입상이 형성되었으며 입자의 크기, 형상은 발광특성에 영향을 미쳤다. 또 $Eu^{ 3+}$ 농도는 7wt%가 최적조건으로 나타났다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.1
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• pp.32-37
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• 2006

Rare-earth niobates, ag (Ln = Y, La, Gd) are well-known self-activated phosphors due to charge transfer in $NbO^{3-}_4$ showing a broad and strong emission band in the spectral region around 410 nm. In order to find new blue and red phosphors for FED, $LaNbO_4$ : X (X = Bi, Eu) phosphors are prepared through solid-state reactions at high temperature. The optimum reaction condition for these phosphors to give maximum emission intensity is obtained when it is first fired at $1250^{\circ}C$ for 2 h followed by second firing at $1400^{\circ}C$ for 1 h. Under irradiation at 254 nm, $1mol\%\;Bi^{3+}$ doped $LaNbO_4$ phosphor shows strong blue emission band with a range of $420\~450nm$. Also $10mol\%\;Eu^{3+}$ doped $LaNbO_4$ phosphor shows the maximum emission intensity at about 610 nm. Emission peaks at $415\~460nm$, $530\~560nm$and $570\~620nm$are observed in phosphors below $10mol\%\;Eu^{3+}$ doped $LaNbO_4$. Similar results are obtained in cathodoluminescent property of these phosphors.