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Synthesis and Characterization of Large Surface Area yttrium oxide by Precipitation Method

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Journal of Rare Earths 2004年第6期22卷 771-774页

作者：崔大立龙志奇张顺利崔梅生黄小卫 Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China

The method for preparing yttrium oxide with large specific surface area was introduced. By means of BET, SEM, TG and DTA analysis, the effects of precipitant, stirring velocity, non-RE impurity in solution, calcination temperature, on the surface area were studied respectively. The Y_2O_3 sample with specific surface area of more than 60 m^2·g^(-1) and L.O.I less than 1% was prepared in the suitable precipitation condition and calcinations temperature when the ammonia used as precipitant. The SEM shows that the Y_2O_3 prepared with large surface area is the aggregation of about 50 nm particles.

关键词： surface area yttrium oxide morphology precipitation method rare earths

Thermal, Mechanical and Electrical Properties of the PEO-based Solid Polymer Electrolytes Filled by yttrium oxide Nanoparticles

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Journal of Wuhan University of Technology(Materials Science) 2012年第3期27卷 495-500页

作者：梁桂杰 Research Center for Materials Science & Engineering Xiangfan University College of Materials Science & Engineering Xi'an Jiaotong University

The novel composite lithium solid polymer electrolytes （SPEs） composed of polyethylene oxide （PEO） matrix and yttrium oxide （Y2O3） nanofillers were prepared by a solution casting method. The crystal morphology of the SPEs was characterized by polarized optical microscope （POM） and wide-angle X-ray diffraction （WAXD）. The induced nucleation and steric hindrance effects of Y2O3 nanofillers result in the increased amount as well as decreased size of PEO spherulites which are closely related to the crystallinity of the SPEs. As the Y2O3 contents increase from 0 wt% to 15 wt%, the crystallinity of the SPEs decreases proportionally. The thermal, mechanical and electrical properties of the SPEs were investigated by thermal gravimetric analysis （TGA）, dynamic mechanical analysis （DMA） and AC impedance method, respectively. The physical properties including thermal, mechanical and electrical performances, depending remarkably on the polymer-filler interactions between PEO and Y2O3 nanoparticles, are improved by different degrees with the increase of Y2O3 contents. The （PEO）21LiI/10 wt%Y2O3 composite SPE exhibits the optimal room-temperature ionic conductivity of 5.95×10-5 Scm-1, which satisfies the requirements of the conventional electrochromic devices.

关键词： solid polymer electrolytes yttrium oxide thermostability mechanical property ionic conductivity

Synthesis and Characterization of Large Surface Area yttrium oxide by Precipitation Method

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Synthesis and Characterization of Large Surface Area Yttrium...

Effect of Y_(2)O_(3)doping on preparation ultrafine/nano-tungsten powder and refinement mechanism

2004国际稀土研究与应用研讨会（包头）

作者：崔大立龙志奇张顺利崔梅生黄小卫 Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China

关键词： surface area yttrium oxide morphology precipitation method rare earths

来源： cnki会议评论

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Tungsten 2023年第4期5卷 539-547页

作者： Dong-Dong Lv Yu Sun Jian-Bo Zhang Sheng-Da Guo Bai-Xiong Liu Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China Jiangxi Advanced Copper Industry Research Institute Yingtan335000China Naional Rare Earh Functional Material Innovation Center Jiangxi Universiy of Science and TechnologyGanzhou341000China Engineering Research Center of Tungsten Resources High-Efficiency Development and Application Technology of the Ministry of Education Jiangxi University of Science and TechnologyGanzhou341000China

In this study,ultrafine/nano W-Y_(2)O_(3)composite powders were synthesized by spray drying,roasting and two-step hydrogen reduction using ammonium metatungstate and yttrium nitrate as raw materials.The mechanism of the influence of Y_(2)O_(3)on the growth of WO_(2.72)and the particle refinement of tungsten powder is discussed.The effect of Y_(2)O_(3)particles on the reduction behavior of tungsten powder was investigated using scanning electron microscopy to study the near surface morphology and X-ray diffraction for phase ID(composition)and crystal structural changes for the reduced powders at each step.The results show that the doping of 0.3 wt.%Y_(2)O_(3)can significantly increase the aspect ratio of WO_(2.72)in the first step of hydrogen reduction.Moreover,Y_(2)O_(3)can effectively inhibit the growth of tungsten particles in the hydrogen reduction process.Therefore,The Y_(2)O_(3)-doped tungsten powders have finer particles and a narrower particle size distribution range than the undoped powders.The average particle diameter of 0.3 wt.%Y_(2)O_(3)doping tungsten powder was in the range of 90-120 nm.

关键词： Tungsten powder Hydrogen reduction yttrium oxide

Microstructure and electrical properties of Y_2O_3-doped ZnO-based varistor ceramics prepared by high-energy ball milling

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Journal of University of Science and Technology Beijing 2007年第3期14卷 266-270页

作者： Hongyu Liu Xueming Ma Dongmei Jiang Wangzhou Shi College of Science Wuhan University of Science and Technology Wuhan 430081 China Department of Physics East China Normal University Shanghai 200062 China

Y2O3-doped ZnO-based varistor ceramics were prepared using high-energy ball milling （HEBM） and low-temperature sin- tering technique, with voltage-gradient of 1934-2197 V/mm, non-linear coefficients of 20.8-21.8, leakage currents of 0.59-1.04 μA, and densities of 5.46-5.57 g/cm3. With increasing Y2O3 content, the voltage-gradient increases because of the decrease of ZnO grain size; the non-linear coefficient and the leakage current improve but the density decreases because of more porosity; the donor con- centration and density of interface states decrease, whereas the barrier height and width increase because of the acceptor effect of Y2O3 in varistor ceramics.

关键词： inorganic materials electrical properties high-energy ball milling varistor microstructure low-temperature sintering zinc oxide yttrium oxide

Preparation and optical properties of Y_2O_3/SiO_2 powder

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Rare Metals 2011年第1期30卷 33-38页

作者： SHEN Xiaoyi ZHAI Yuchun School of Materials and Metallurgy Northeastern UniversityShenyang 110819China

Y（NO3）3 and NH3·H2O were used as a raw materials,and nano-Y2O3 powder was successfully synthesized by a precipitation method.Employing TEOS as a raw material,SiO2 powder was successfully prepared by a alkoxide-hydrolysis method,and a Y2O3/SiO2 composite powder was obtained by coating.The Y2O3,SiO2,and Y2O3/SiO2 powders were characterized using X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and Fourier transform infrared spectrophotometer（FT-IR）;the Y2O3 and Y2O3/SiO2 powders were further examined by photoluminescence（PL） spectra.The results indicated that the Y2O3 powder had a body-centered cubic structure with an average size of 35 nm,while the SiO2 powder was amorphous,with an average size of 145 nm and a narrow size distribution.The PL spectra of the Y2O3 and Y2O3/SiO2 powders showed that their wavelength of emission spectra were 585 nm,while their wavelength of excitation spectra were in the range of 240-260 nm.The optical properties of the Y2O3/SiO2 powder were identical to the Y2O3 powder.

关键词： powders composite materials yttrium oxide silicon oxide optical properties

Reduction of Tb^4+ ions in luminescent Y2O3:Tb nanorods prepared by microwave hydrothermal method

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Journal of Rare Earths 2016年第8期34卷 774-781页

作者： Jaroslaw Kaszewski Bartlomiej S. Witkowski Lukasz Wachnicki Hanka Przybylinska Boleslaw Kozankiewicz Ewa Mijowska Marek Godlewski Institute of Physics Polish Academy of Sciences al. Lotnik6w 32/46 02-668 Warsaw Poland Institute of Chemical and Environment Engineering West Pomeranian University of Technology ul. Putaslego 10 70-322 Szczecin Poland

Terbium doped yttrium oxide was prepared with the microwave hydrothermal method. The Y2O3：Tb nanomaterial crystal- lized as needle-like grains. Bright luminescence in the green region was observed. Significant luminescence intensity increase was obtained after thermal treatment. Reduction of terbium ions was observed after heating in the air atmosphere. Tb4＋ ions were found to be stabilized by crystal impurities. Hydroxyl species were found to have impact on vacancies elimination. The terbium ions were used as optical and magnetic indicator of the material properties.

关键词： yttrium oxide terbium luminescence biomarkers abnormal reduction rare earths

Electrochemical preparation and characterization of brain-like nanostructures of Y_2O_3

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Journal of Rare Earths 2013年第3期31卷 281-288页

作者： Mustafa Aghazadeh Mojtaba Hosseinifard Mohammad Hassan Peyrovi Behrouz Sabour Department of Chemistry Islamic Azad UniversityShar-e-Ray BranchTehranIran Department of Chemistry Faculty of ScienceShahid Beheshti UniversityG.C.P.O.Box 19396-4716TehranIran

Nanostructured Y203 was successfully prepared via a two-step and template-free method. Firstly, yttrium hydroxide precursor was galvanostatically grown on the steel substrate from chloride bath by direct and pulse current deposition modes. Direct cunent deposition was carried out at the constant current density of 0.1 A/dm2 for 600 s. The pulse current was also performed at a typical on-time and off-time （ton=l S and Germ s） with an average current density of 0.05 A/dm2 （la=0.05 A/din2） for 600 s. The obtained hydroxide films were then scraped from the substrates and thermally converted into final oxide product via heat-treatment. Thermal behaviors and phase transformations during the heat treatment of the hydroxide powder samples were investigated by differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）. The final oxide products were characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and scanning electron microscopy （SEM）. The results showed that the well-crystallized Y203 with brainand sphere-like morphology were achievable via pulse and direct deposition modes, respectively. It was concluded that pulse current cathodic electrodeposition offered a facile route for preparation ofnanostructured Y203.

关键词： cathodic electrodeposition heat-treatment electrochemical growth yttrium oxide brain-like nanostructure rare earths

Enhancing Li NiO_(2) cathode materials by concentration-gradient yttrium modification for rechargeable lithium-ion batteries

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Journal of Energy Chemistry 2021年第12期30卷 312-319,I0007页

作者： Yudong Zhang Hang Li Junxiang Liu Jiuding Liu Hua Ma Fangyi Cheng Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Engineering Research Center of High-efficiency Energy Storage(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China Tianjin EV Energies Company Limited(JEVE) Tianjin 300380China

Lithium nickel oxide(LiNiO_(2)) cathode materials are featured with high capacity and low cost for rechargeable lithium-ion batteries but suffer from severe interface and structure instability.Here we report that rationally designed LiNiO_(2) via concentration-gradient yttrium modification exhibits alleviative side reactions and improved electrochemical performance.The LiNiO_(2) cathode with LiYO_(2)-Y_(2) O_(3) coating layer delivers a discharge capacity of 225 mAh g^(-1) with a high initial Coulombic efficiency of 93.4%.These improvements can be attributed to the formation of in-situ modified hybrid LiYO_(2)-Y_(2 O3) coating layer,which suppresses phase transformation,electrolyte oxidation and salt dissociation due to the formation of protective cathode electrolyte interface.The results indicate promising application of concentration-gradient yttrium coating as a facile approach to stabilize nickel-rich cathode materials.

关键词： Lithium-ion battery Concentration gradient Nickel-rich cathode Surface coating yttrium oxide