• Title/Summary/Keyword: Nd-doped

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I-V Characteristics of Praseodymium-Based ZnO Varistors Doped with Neodymium (네오디뮴이 첨가된 프라세오디뮴계 ZnO 바리스터의 I-V 특성)

  • 박춘현;윤한수;남춘우
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.312-316
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    • 1999
  • I-V characteristics of Praseodymium-based ZnO varistor doped with $Nd_2O_3$ in the range 0.0-2.0mol% sintered at 130$0^{\circ}C$ and 135$0^{\circ}C$ were investigated. In the all sides, ZnO varistors sintered at $1300^{\circ}C$ exhibited much better varistor characteristics than that at 135$0^{\circ}C$. All ZnO varistors doped with $Nd_2O_3$ sintered at $1300^{\circ}C$ exhibited good varistor characteristics but particularly ZnO varistor doped with l.Omol% $Nd_2O_3$ exhibited the best characteristics, which the nonlinear is 65.2 and the leakage current is 4.5pA. It is estimated that ZnO varistor doped with l.Omol% $Nd_2O_3$ will begin to be sufficiently used as basic composition to fabricate a good varistor.

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Neodymium doped mixed metal oxide derived from CoAl-layered double hydroxide: Considerable enhancement in visible light photocatalytic activity

  • Khodam, Fatemeh;Amani-Ghadim, Hamid Reza;Aber, Soheil;Amani-Ghadim, Ali Reza;Ahadzadeh, Iraj
    • Journal of Industrial and Engineering Chemistry
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    • v.68
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    • pp.311-324
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    • 2018
  • Herein,the Neodymium ion ($Nd^{3+}$) doped CoAl-LDH have been successfully prepared via co-precipitation method and was used as a precursor of Nd-doped CoAl-mixed metal oxides (MMO). The photocatalytic activity of doped LDH and MMO was investigated in the degradation of an azo dye, C.I. Acid Red 14, under visible light irradiation. DRS and PL analysis demonstrated decreasing in the band gap energy and recombination of photo-induced charge carriers of Nd-doped LDH and MMO compared with the pristine CoAL-LDH. Due to significant difference in photocatalytic performance. A power law empirical kinetic model was obtained for predicting the photocatalytic degradation efficiency.

Effect of Single and Dual Doping of Rare Earth Metal Ce and Nd Elements on Electrochemical Properties of LiNi0.83 Co0.11Mn0.06O2Cathode Lithium-ion Battery Material (리튬이온전지용 양극활물질 LiNi0.83 Co0.11Mn0.06O2의 전기화학적 특성에 미치는 Ce와 Nd 희토류 금속의 단독 혹은 이중 도핑효과)

  • Kim, Yoo-Young;Ha, Jong-Keun;Cho, Kwon-Koo
    • Journal of Powder Materials
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    • v.26 no.1
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    • pp.49-57
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    • 2019
  • Layered $LiNi_{0.83}Co_{0.11}Mn_{0.06}O_2$ cathode materials single- and dual-doped by the rare-earth elements Ce and Nd are successfully fabricated by using a coprecipitation-assisted solid-phase method. For comparison purposes, non-doping pristine $LiNi_{0.83}Co_{0.11}Mn_{0.06}O_2$ cathode material is also prepared using the same method. The crystal structure, morphology, and electrochemical performances are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) mapping, and electrochemical techniques. The XRD data demonstrates that all prepared samples maintain a typical ${\alpha}-NaFeO_2$-layered structure with the R-3m space group, and that the doped samples with Ce and/or Nd have lower cation mixing than that of pristine samples without doping. The results of SEM and EDS show that doped elements are uniformly distributed in all samples. The electrochemical performances of all doped samples are better than those of pristine samples without doping. In addition, the Ce/Nd dual-doped cathode material shows the best cycling performance and the least capacity loss. At a 10 C-rate, the electrodes of Ce/Nd dual-doped cathode material exhibit good capacity retention of 72.7, 58.5, and 45.2% after 100, 200, and 300 cycles, respectively, compared to those of pristine samples without doping (24.4, 11.1, and 8.0%).

Microstructure and Electrical Properties of $Pr_6$$O_{11}$-Based ZnO Varistors Doped with $Nd_24$O_3$ ($Nd_24$O_3$가 첨가된 $Pr_6$$O_{11}$계 ZnO 바리스터의 미세구조 및 전기적 성질)

  • 남춘우;박춘현;윤한수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.3
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    • pp.206-213
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    • 2000
  • The microstructure and electrical properties of Pr$_{6}$/O sub 11/-Based ZnO varistors with Nd$_2$O$_3$ was doped in the range of 0.0 to 2.0 mol% were investigated. Most of the added Nd$_2$O$_3$were segregated at the nodal points and grain boundaries and were found to form the Nd-rich phase. In addition the bulk intergranular layer at the grain boundaries and nodal points was consisted of Nd-rich phase and Pr-rich phase. the average grain size was decreased in the range of 7.8 to 5.6${\mu}{\textrm}{m}$ with increasing Nd$_{2}$/O sub 3/ additive content. The nonlinearity of ZnO varistors sintered at 130$0^{\circ}C$ was much more excellent than that at 135$0^{\circ}C$ ZnO varistors doped with 1.0mol% Nd$_{2}$/O sub 3/ exhibited the best nonlinearity. which is 65.2 in the nonlinear exponent and 4.5$\mu$A in the leakage current. Consequently. it is estimated that Pr$_{6}$/O sub 11/ -based ZnO varistors doped with 1.0 mol% Nd$_{2}$/O sub 3/ are to be sufficiently used as basic composition to fabricate good varistors in the future.ure.

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Magnetic Properties and Impedance Spectroscopic Studies of Multiferroic Bi1-xNdxFeO3 Materials

  • Thang, Dao Viet;Thao, Du Thi Xuan;Minh, Nguyen Van
    • Journal of Magnetics
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    • v.21 no.1
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    • pp.29-34
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    • 2016
  • Nd-doped $BiFeO_3$ materials were synthesized via a sol-gel method. The crystal structure, magnetic properties, and complex impedance spectroscopy of multiferroic $Bi_{1-x}Nd_xFeO_3$ (BNFO) materials were investigated by X-ray diffraction (XRD), Raman scattering, vibrating sample magnetometer (VSM), and complex impedance spectroscopy. Our results show that the lattice crystal constants (a, c) and the ratio c/a of BNFO materials decreased with increasing Nd concentration. All samples exhibited weak ferromagnetism at room temperature, and the magnetization of samples was enhanced by the presence of $Nd^{3+}$ ions. There was an enhancement in the spontaneous magnetization of BFO with increasing Nd concentration, which is attributable to the collapse of the spin cycloid structure.

Optical Characterization on Undoped and Mg-doped GaN Implanted with Nd (Nd이 이온주입된 undoped와 Mg-doped GaN의 분광 특성 연구)

  • Song, Jong-Ho;Rhee, Seuk-Joo
    • Journal of the Korean Vacuum Society
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    • v.15 no.6
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    • pp.624-629
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    • 2006
  • The energy transfer process between GaN and Nd ions as well as Mg codoping effect were investigated in Nd-implanted GaN films. Photoluminescence (PL) and PL excitation spectroscopies were performed on $^4F_{3/2}{\rightarrow}^4I_{9/2}$ Nd ionic level transition. At least three below bandgap traps were identified in the energy transfer process. The number of one particular trap, which is assigned to be an isoelectronic Nd trap, is increased with the Mg-codoping. The emission efficiency with above gap excitation, which emulates the electrical excitation, is further increased in GaN:Mg,Nd.

Efficient Second Harmonic Generation of Pulsed Nd-YAG Laser Radiation with Noncritically Phase-Matchable $LiNbO_3$ in Room-Temperature

  • Jong-Soo Lee;Bong-Hoon Kang;Bum Ku Rhee;Chong-Don Kim;Gi-Tae Joo
    • The Korean Journal of Ceramics
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    • v.6 no.3
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    • pp.206-208
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    • 2000
  • 0.65 mol% MgO-doped LiNbO$_3$single crystals were grown by CZ method. The obtained single crystals were colorless and transparent. Noncritically phase-matched second harmonic generation (SHG) of 532-nm radiation from 1064-nm in MgO-doped LiNbO$_3$has been investigated by using pulsed Nd:YAG laser. The phase-matching temperature was room temperature. SHG conversion efficiencies were typically achieved higher than 50% at the phase-matching temperature with no photorefractive damage in the region of fundamental power density which was used in this experiment. The thermo-birefringence coefficient and the electro-birefringence coefficient of SHG were calculated from the temperature phase-matching profile with the electric field.

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Crystal Growth and Photoluminescence Property of Stoichiometric LiNbO3 Single Crystal Fiber by Addition of Nd2O3 (Nd\2O3 첨가에 따른 화학양론조성 LiNbO3 단결정의 성장 및 형광특성)

  • Shur, Joong-Won;Yoon, Seok-Gyu;Lee, Sung-Mun;Yoon, Dae-Ho
    • Journal of the Korean Ceramic Society
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    • v.39 no.10
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    • pp.977-980
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    • 2002
  • Using the micro-pulling down method, $Nd_2O_3$ doped crack-free stoichiometric $LiNbO_3$ single crystals were grown in 1 mm diameter and 30∼35 mm length. The homogeneous distributions of $Nd_2O_3$ concentration were confirmed by the electron probe micro analysis. The absorption and photoluminescence spectra were measured with respect to the $Nd_2O_3$ doping.

Laser annealing on ZnO:P thin films (ZnO:P 박막의 레이저 어닐링 연구)

  • Chang, Hyun-Woo;Kang, Hong-Seong;Kim, Gun-Hee;Lim, Sung-Hoon;Lee, Sang-Yeol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.51-52
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    • 2005
  • Phosphorus doped ZnO thin films on (001) $Al_2O_3$ substrate have been prepared by a pulsed laser deposition (PLD) technique using a Nd:YAG laser. After deposition, phosphorus doped ZnO thin films have been annealed in vacuum, air, nitrogen, and oxygen ambients using pulsed Nd:YAG laser. We report the electrical properties of phosphorus doped ZnO thin films with the variation of the laser annealing conditions for the applications of optoelectronic devices.

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Effects of $PbTiO_3$ Addition on Dielectric Properties and Extent of PbO Loss in Nd-Doped $Pb(Mg^{1/3}Nb^{2/3})O_3$ System ($Nd^{3+}$로 치환된 $Pb(Mg^{1/3}Nb^{2/3})O_3$$PbTiO_3$ 첨가에 따른 유전특성과 PbO 휘발)

  • 김성열;이응상
    • Journal of the Korean Ceramic Society
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    • v.30 no.8
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    • pp.671-677
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    • 1993
  • Effects of PbTiO3 addition on dielectric properties and extent of PbO loss in Nd-doped Pb(Mg1/3Nb2/3)O3 system were investigated. As the proportion of dopping increased, the phase transition temperature shifted to low region, and the dielectric constant at room temperature decreased rapidly. But as the proportion of PbTiO3 increased, the phase transition temperature shifted to high retion, and the dielectric constant at room temperature increased. The substitution of Nd3+ for Pb2+ decreased the amount of PbO evaporation, therefore the sample sintered well in case of only 1 mole% adding excess PbO.

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