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Enhanced thermal stability of Ce_(0.33)Zr_(0.55)(LaNdY)_(0.12)O_(2) mixed oxides prepared by sulfate-aided coprecipitation method 被引量:5
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作者 Shilei Chen Yongke Hou +4 位作者 Hao Wang Zheng Zhao Yongqi Zhang Juanyu Yang Xiaowei Huang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第5期587-595,共9页
Ceria-zirconia based mixed oxides(CZs)have been applied in three-way catalysts(TWCs)for their high surface area and oxygen storage capacity(OSC).In this work,enhanced thermal stability of Ce_(0.33)Zr_(0.55)(LaNdY)_(0.... Ceria-zirconia based mixed oxides(CZs)have been applied in three-way catalysts(TWCs)for their high surface area and oxygen storage capacity(OSC).In this work,enhanced thermal stability of Ce_(0.33)Zr_(0.55)(LaNdY)_(0.12)O_(2)mixed oxides was realized via a facile and scalable approach,namely,sulfateaided coprecipitation method was labelled as CZ-S.Sulfate ion(SO_(4)^(2-))was added into raw solution in the form of sulfuric acid and acted as coordination agent.The control sample was prepared by conventional coprecipitation method without sulfuric acid added and labelled as CZ.The promotion effect of sulfate ion was analyzed systematically by X-ray diffraction(XRD),transmission electron microscopy(TEM),scanning electron microscopy(SEM),N_(2)adsorption-desorption,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),OSC and hydrogen temperatureprogrammed reduction(H_(2)-TPR)analysis.XRD and high resolution TEM results reveal that CZ-S have homogeneous distributions of elements.TEM and SEM images show that fresh samples of CZ-S have narrower distributions of grain sizes and larger pore sizes than those of CZ.Through cross analysis of structure and morphology of CZ and CZ-S,we find that the introduction of sulfate ions results in uniform distributions of elements,narrows distributions of grain sizes,and enables the formation of secondary loose packing of sub-particles,which lead to enhanced thermal stability of the samples of CZ-S upon aging process at high temperature.After aging treatment at 1100℃for 10 h,aged samples of CZ-S present larger specific surface areas and pore volumes than the aged sample prepared by conventional coprecipitation method without sulfate ions added.Furthermore,the aged sample of CZ-S2(SO_(4)^(2-)/Zr=1)possesses the highest specific surface area of 21.9 m2/g and the biggest pore volume of 0.035 mL/g among all aged samples. 展开更多
关键词 Ceria-zirconia based mixed oxides Sulfate-aided coprecipitation method Specific surface area Thermal stability Rare earths
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Studies on State and Structure of Noble Metals in Electrocatalyst Made by Coprecipitation Method 被引量:1
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作者 HOU Zhong-jun +1 位作者 LEI Hao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期89-93,共5页
The electrocatalysts of Pt/C, PtRu/C and Ru/C were prepared by the impregnation method. The facet characterization, the dispersion and the particle size for the catalysts were determined by means of X ray diffractio... The electrocatalysts of Pt/C, PtRu/C and Ru/C were prepared by the impregnation method. The facet characterization, the dispersion and the particle size for the catalysts were determined by means of X ray diffraction and transmission electron microscopy. X ray photoelectron spectroscopy was also used to analyze the state and the valency of the noble metals. The results show that the particle size was in nanometer range and the binary metals have come into being an alloy. The platinum in the catalysts existed in zero valency. The valency of the ruthenium on the surface is different from that in the body, while the ruthenium on the surface existed in oxide form. PtRu/C and Pt/C are of good activity to the electrooxidation of hydrogen except Ru/C. PtRu/C is more tolerant of CO than Pt/C, and CO is only adsorbed on Pt. 展开更多
关键词 Proton exchange membrane fuel cell coprecipitation method ELECTROCATALYST PTRU/C XPS
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Microstructure and magnetic characteristics of nanocrystalline Ni0.5Zn0.5 ferrite synthesized by a spraying-coprecipitation method 被引量:2
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作者 刘银 丘泰 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3837-3842,共6页
Nanocrystalline Ni0.5Zn0.5 ferrite with average grain sizes ranging from 10 to 100 nm is prepared by using a spraying-coprecipitation method. The results indicate that the nanocrystalline Ni0.5Zn0.5 ferrite is ferroma... Nanocrystalline Ni0.5Zn0.5 ferrite with average grain sizes ranging from 10 to 100 nm is prepared by using a spraying-coprecipitation method. The results indicate that the nanocrystalline Ni0.5Zn0.5 ferrite is ferromagnetic without the superparamagnetic phenomenon observed at room temperature. Specific saturation magnetization of nanocrystalline Nio.sZno.5 ferrite increases from 40.2 to 75.6 emu/g as grain size increases from 11 to 94nm. Coercivity of nanocrystalline Ni0.5Zn0.5 ferrite increases monotonically when d 〈 62 nm.The relationship between the coercivity and the mean grain size is well fitted into a relation Hc - d^3. A theoretically evaluated value of the critical grain size is 141nm larger than the experimental value 62nm for nanocrystalline Ni0.5Zn0.5 ferrite. The magnetic behaviour of nanocrystalline Ni0.5Zn0.5 ferrite may be explained by using the random anisotropy theory. 展开更多
关键词 nanocrystalline material Ni0.5Zn0.5 ferrite spraying-coprecipitation method
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Preparation of tetragonal CaO-ZrO_2 nano-powder by chemical coprecipitation method 被引量:1
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作者 刘建本 阮建明 +2 位作者 邹俭鹏 李亚军 骆锋 《中国有色金属学会会刊:英文版》 EI CSCD 2003年第3期600-604,共5页
With zirconium oxychloride, nitrate of lime and ammonia as raw materials, nano powder of CaO ZrO 2 was prepared by chemical coprecipitation method. By use of azeotropic distillation processing, chemical coprecipitatio... With zirconium oxychloride, nitrate of lime and ammonia as raw materials, nano powder of CaO ZrO 2 was prepared by chemical coprecipitation method. By use of azeotropic distillation processing, chemical coprecipitation precursor was obtained. Phase transformation of the precursor was observed at the temperature of 593.81 ℃ and 1 234.56 ℃ respectively with DTA analyses. Phase structure was analyzed through XRD and Raman spectra. The average particle size of tetragonal zirconium oxide powder was 9.8 and 43.7 nm after calcination at 600 and 1 100 ℃ respectively which was tested by TEM and BET analyses. Furthermore, the influences of the doping of nitrate of lime and the average particle size of zirconium oxide on the stability of tetragonal zirconium oxide were also discussed. 展开更多
关键词 正方晶系 CaO-Zr02陶瓷 预处理 化学共沉淀 纳米粉末 相变
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Effect of Zn^(2+) Content on the Microstructure and Magnetic Properties of Nanocrystalline Ni_(1-x)Zn_xFe_2O_4 Ferrite by a Spraying-coprecipitation Method 被引量:1
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作者 刘银 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期429-431,共3页
Nanocrystalline Ni1-xZnxFe2O4 ferrites with 0≤x≤1 were successfully prepared by a spraying-coprecipitation method.The microstructure was investigated by using XRD and TEM.Magnetic properties were measured with vibra... Nanocrystalline Ni1-xZnxFe2O4 ferrites with 0≤x≤1 were successfully prepared by a spraying-coprecipitation method.The microstructure was investigated by using XRD and TEM.Magnetic properties were measured with vibrating sample magnetometer(VSM) at room temperature.The results show that the grain size of nanocrystalline Ni1-xZnxFe2O4 ferrite calcined at 600 ℃ for 1.5 h is about 30 nm.Lattice parameter and specific saturation magnetization Ms of nanocrystalline Ni1-xZnxFe2O4 ferrite increase with the Zn^2+ ions content at room temperature,and maximum Ms is 66.8 A·m^2·kg^-1 as the Zn^2+ ions content is around 0.5,and coercivity Hc of the nanocrystalline Ni1-xZnxFe2O4 ferrite decreases with Zn^2+ ions content. 展开更多
关键词 nanocrystalline material Ni-Zn ferrite spraying-coprecipitation method magnetic properties MICROSTRUCTURE
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Comparison of LiNi_(0.5)Mn_(1.5)O_4 cathode materials prepared by different coprecipitation methods
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作者 孙强 王志兴 +2 位作者 李新海 郭华军 彭文杰 《中国有色金属学会会刊:英文版》 CSCD 2007年第A02期917-922,共6页
LiNi0.5Mn1.5O4 was synthesized by two different coprecipitation methods:composite carbonate process and composite hydroxide method. The effects of calcination temperature of precursors on the physical properties and e... LiNi0.5Mn1.5O4 was synthesized by two different coprecipitation methods:composite carbonate process and composite hydroxide method. The effects of calcination temperature of precursors on the physical properties and electrochemical performance of the samples were investigated. The results of scanning electron microscopy(SEM) show that as calcination temperature increases,the crystallinity of the samples is improved,and their grain sizes are obviously increased. X-Ray diffraction(XRD) data show that the LiNi0.5Mn1.5O4 compounds obtained by two coprecipitation methods both exhibit a pure cubic spinel structure without any impurities. Furthermore,it is found that the samples prepared with relatively high temperature precursors present large initial discharge capacity(>125 mA·h/g) and excellent cycling stability with a capacity retention rate larger than 91% after 30 cycles at current density of 1 C. This probably derives from their higher crystallinity and larger grain sizes. However,the initial discharge capacity of LiNi0.5Mn1.5O4 synthesized by composite carbonate process is smaller than that prepared by composite carbonate process,but it shows better capacity retention ability. 展开更多
关键词 锂离子电池 阴极材料 制备 沉积方法 锂镍锰氧化物
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A Coprecipitation Coating Synthesis of SiC/YAG Composites 被引量:1
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作者 NingZHANG HongqiangRU +1 位作者 XudongSUN QingkuiCAI 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第3期323-326,共4页
The α-SiC in 0.5μm size powders were coated with Al_2O_3 and Y_2O_3 by a coprecipitation coating (CPC) method forfabrication of SiC/YAG composites. The same powder preparation was carried out by conventional mechani... The α-SiC in 0.5μm size powders were coated with Al_2O_3 and Y_2O_3 by a coprecipitation coating (CPC) method forfabrication of SiC/YAG composites. The same powder preparation was carried out by conventional mechanical mixing(MM) method for comparison. Two kinds of SiC/YAG composites were manufactured by pressureless sintering usingthe different powders, named CPC composite and MM composite thereafter respectively. It is shown that the CPCcomposite has the advantages of homogeneous distribution of YAG phase and of being sintered to high density ata low temperature, 100℃ lower than that of MM composite. The strength (573 MPa) and hardness (23.3 GPa) ofthe CPC composite are significantly higher than those (323 MPa and 13.5 GPa) of the MM composite, respectively. 展开更多
关键词 coprecipitation SiC/YAG composites Mechanical mixing method
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Synthesis and Tribological Properties of Copper-alumina Nanocomposites Prepared by Coprecipitation Technique
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作者 符学龙 HU Yubing 陶杰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第5期1123-1130,共8页
The objective of this work is to study the synthesis of copper-alumina nanocomposites using the coprecipitation process and hot-pressing method, and investigate their mechanical properties. The effects of calcination ... The objective of this work is to study the synthesis of copper-alumina nanocomposites using the coprecipitation process and hot-pressing method, and investigate their mechanical properties. The effects of calcination temperature on the average size of composite particles and chemical composition after calcination were also analyzed. The sintering parameters including sintering temperature, hot pressure and packing time were optimized to fabricate the alumina nanoparticles reinforced copper matrix composites(CMCs). The density, microhardness and tribological properties of the CMCs reinforced with 1 wt%, 2 wt%, 3 wt%, 4 wt% and 5 wt% of alumina nanoparticles were investigated correspondingly. The results showed that the optimum preparation parameters for the CMCs were 900 ℃ of hot pressing temperature, 27.5 MPa of hot pressure and 2 hrs of packing time. The CMC reinforced with 2 wt% of alumina nanoparticles had the lowest wear rate, with the relative wear resistance of 3.13. 展开更多
关键词 copper matrix composites alumina nanoparticles wear rate coprecipitation method
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碳酸钠共沉淀法制备镍钴锰酸锂三元正极材料的研究
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作者 韦世菊 邓园园 +2 位作者 全军 谢雪珍 马皓皓 《山东化工》 2026年第1期46-51,共6页
以硫酸锰、硫酸钴、硫酸镍、氨水为主要原料,碳酸钠作为沉淀剂,通过单因素实验、正交试验,以pH值、锂过量百分比、煅烧温度及陈化时间为变量,研究不同因素对三元前躯体振实密度的影响,通过试验得到的最佳参数:陈化时间为1 h,pH值为8.0,... 以硫酸锰、硫酸钴、硫酸镍、氨水为主要原料,碳酸钠作为沉淀剂,通过单因素实验、正交试验,以pH值、锂过量百分比、煅烧温度及陈化时间为变量,研究不同因素对三元前躯体振实密度的影响,通过试验得到的最佳参数:陈化时间为1 h,pH值为8.0,锂过量百分比为8%,煅烧温度为900℃,在此条件下前驱体的振实密度可高达2.699 g/mL。XRD和电镜分析结果表明,锂过量百分比8%时,材料具有良好的α-NaFeO_(2)型层状结构的纯相;制得的正极颗粒形貌规则,呈现出类球状,粒径分布均匀,有利于提升电化学性能。 展开更多
关键词 共沉淀法 正极材料 前驱体 高镍三元材料
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A Cost-Effective Co-precipitation Method for Synthesizing Indium Tin Oxide Nanoparticles without Chlorine Contamination 被引量:8
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作者 Haiwen Wang Xiujuan Xu +1 位作者 Jianrong Zhang Chunzhong Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2010年第11期1037-1040,共4页
Indium tin oxide (ITO) nanoparticles with crystallite size of 12.6 nm and specific surface area of 45.7 m 2 ·g-1 were synthesized by co-precipitation method.The indium solution was obtained by dissolving metal ... Indium tin oxide (ITO) nanoparticles with crystallite size of 12.6 nm and specific surface area of 45.7 m 2 ·g-1 were synthesized by co-precipitation method.The indium solution was obtained by dissolving metal indium in HNO3.The tin solution was obtained by dissolving metal tin in HNO3 and followed by stabilizing with citric acid.The free of chlorine ions in the synthesis process brought several advantages:shortening the synthesis time,decreasing the particle agglomeration,decreasing the chlorine content in the ITO nanoparticles and improving the particle sinterability.This is the first time to report the synthesis of ITO nanoparticles free from chlorine contamination without using the expensive metal alkoxides as starting materials. 展开更多
关键词 NANOMATERIALS Powder technology Indium tin oxide coprecipitation method
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Controlled Preparation of Monodisperse CoFe_2O_4 Nanoparticles by a Facile Method
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作者 王海 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第2期258-262,共5页
CoFe2O4 nanoparticles (NPs) were synthesized by coprecipitation method using FeCl3·6H2O and CoCl2·6H2O as precursors.The synthesized conditions were optimized,such as added means of precipitator,quantity o... CoFe2O4 nanoparticles (NPs) were synthesized by coprecipitation method using FeCl3·6H2O and CoCl2·6H2O as precursors.The synthesized conditions were optimized,such as added means of precipitator,quantity of precipitator,the mol ratio of Fe 3+ to Co2+,reaction temperature and pH value.The synthesized material was characterized by XRD,TEM,FTIR,EDS,Raman and its magnetic properties were studied by VSM.The experimental results confirm that the sample is cubic spinel structure CoFe2O4 with a narrow size distribution and a good dispersion feature.CoFe2O4 NPs with well-controlled shape and size was obtained at 70℃.The magnetic properties indicate superparamagnetic behavior and good saturated magnetization. 展开更多
关键词 CoFe2O4 nanoparticles coprecipitation method MONODISPERSITY SUPERPARAMAGNETISM
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Cu-La-Al尖晶石催化剂的甲醇水蒸气重整制氢反应性能 被引量:1
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作者 武文杰 冯阳 +5 位作者 王俊刚 陈从标 马中义 郗宏娟 侯博 杨晓峰 《洁净煤技术》 北大核心 2025年第5期134-144,共11页
在甲醇水蒸气重整制氢(MSR)反应中,Cu-Al尖晶石催化剂因具有低成本和高选择性的特点,使其成为该反应的理想催化剂,但其催化性能还有待进一步提高。采取共沉淀法、溶胶-凝胶法和浸渍法制备了Cu-Al尖晶石催化剂,并将其用于MSR反应中。结... 在甲醇水蒸气重整制氢(MSR)反应中,Cu-Al尖晶石催化剂因具有低成本和高选择性的特点,使其成为该反应的理想催化剂,但其催化性能还有待进一步提高。采取共沉淀法、溶胶-凝胶法和浸渍法制备了Cu-Al尖晶石催化剂,并将其用于MSR反应中。结果表明,共沉淀法制备的Cu-Al尖晶石催化剂在MSR反应中表现出优异的性能,这是由于其比表面积最大,有利于活性位点的暴露。在此基础上,用不同摩尔分数的稀土元素La对共沉淀法制备的Cu-Al尖晶石催化剂进行了改性。结果表明,稀土元素La的引入不仅能进一步提升催化剂的比表面积,还会导致Cu-Al尖晶石微观结构发生变化。由于部分La进入尖晶石结构中,从而改变了Cu-Al尖晶石阳离子的分布情况,并使晶粒尺寸减小。因此,添加适量的稀土元素La可以提升Cu-Al尖晶石的MSR反应性能,而过量的La会导致催化剂表面形成LaAlO3,从而降低催化剂的活性。 展开更多
关键词 共沉淀法 Cu-La-Al尖晶石 甲醇水蒸气重整制氢 制氢 催化剂
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制备方法对La_(2)O_(2)CO_(3)/ZnO催化乙醇脱氢性能的影响 被引量:1
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作者 屈鑫茹 薄德臣 +2 位作者 耿忠兴 白国玉 刘冬梅 《石油化工高等学校学报》 2025年第4期66-74,共9页
针对乙醇催化脱氢制备乙醛的反应,现有催化剂存在选择性受限的问题,特别是在高效生成乙醛方面表现不佳,部分催化剂因酸度过高而阻碍脱氢过程。因此,开发具有表面碱性的新型高性能催化剂至关重要。通过共沉淀法与溶液燃烧法分别制备了La_... 针对乙醇催化脱氢制备乙醛的反应,现有催化剂存在选择性受限的问题,特别是在高效生成乙醛方面表现不佳,部分催化剂因酸度过高而阻碍脱氢过程。因此,开发具有表面碱性的新型高性能催化剂至关重要。通过共沉淀法与溶液燃烧法分别制备了La_(2)O_(2)CO_(3)/ZnO-a和La_(2)O_(2)CO_(3)/ZnO-b两种复合催化剂,通过改变沉淀pH、老化时间、煅烧温度、煅烧时间等条件对催化剂性能进行评价,确定了催化剂的最佳制备条件;利用扫描电镜、透射电镜、X射线衍射、CO_(2)程序升温脱附等手段,深入探究了催化剂的晶相、形貌、表面碱性及其与催化性能的关系;在最佳催化剂上考察了乙醇脱氢反应合成乙醛的最佳工艺条件。结果表明,共沉淀法的最佳制备条件:沉淀pH为9.0,老化时间为12.0 h,n_(La)/n_(Zn)=1.0,煅烧温度为600℃;溶液煅烧法的最佳制备条件:煅烧时间为5.0 h,煅烧温度为550℃,n_(La)/n_(Zn)=1.0;当体积空速为1.0 h^(-1)、反应压力为1.0 MPa、反应温度为190℃时,La_(2)O_(2)CO_(3)/ZnO-a上乙醛的收率最高,为57.60%。 展开更多
关键词 乙醇脱氢制乙醛 共沉淀法 溶液燃烧法 La_(2)O_(2)CO_(3)/ZnO
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Properties and microstructure of oxide dispersion strengthened tungsten alloy prepared by liquid-phase method:a review 被引量:3
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作者 Liu-Jie Xu Zhou Li +3 位作者 Fang-Nao Xiao Yun-Chao Zhao Yu-Cheng Zhou Shi-Zhong Wei 《Tungsten》 EI CSCD 2023年第4期481-502,共22页
The addition of the second phase into tungsten can significantly refine the grain size of tungsten alloys,and also play a role in dispersion strengthening,thus improving the properties of tungsten alloy.As a preparati... The addition of the second phase into tungsten can significantly refine the grain size of tungsten alloys,and also play a role in dispersion strengthening,thus improving the properties of tungsten alloy.As a preparation method of tungsten alloy powder,liquid-phase method avoids the disadvantage of mechanical alloying,and the obtained powder composition is accurate and controllable,with high purity and excellent uniformity.At present,the second phase particles used for dispersion strengthening tungsten alloys are mainly composed of oxides.Oxide particles can be synthesized and precipitated in nitrate solution through in situ chemical reaction,and are uniformly distributed in composite powder by mixing and stirring.Finally,the oxide dispersion strengthened tungsten alloy(ODS-W)was obtained by reduction and sintering.Liquid-phase methods for preparing ODS-W alloys include azeotropic distillation,sol-gel methods,freeze-drying,hydrothermal synthesis,spray-drying,etc.In this paper,several liquid-phase methods for preparing tungsten alloy composite powder precursors are reviewed,and their latest research progresses are discussed.In addition,the morphologies and properties of tungsten alloys prepared by different methods are compared,which provides guidance for preparing high-performance tungsten alloys. 展开更多
关键词 Tungsten alloy ODS-W liquid-phase method MICROSTRUCTURE PROPERTY
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PEG辅助沉淀法制备YPO_(4)∶Er^(3+),Yb^(3+)上转换发光粉和发光性质
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作者 徐振庭 张洋珲 +1 位作者 韩昆伯 李艳红 《化工新型材料》 北大核心 2025年第6期166-172,共7页
采用共沉淀法,以聚乙二醇(PEG)为分散剂制备了前驱体,后经800℃热处理获得了系列YPO_(4)∶Er^(3+),Yb^(3+)上转换发光粉。X射线衍射(XRD)结果表明:所有的样品均为四方结构的YPO_(4)相。PEG对样品的晶粒尺寸有影响。扫描电镜(SEM)结果表... 采用共沉淀法,以聚乙二醇(PEG)为分散剂制备了前驱体,后经800℃热处理获得了系列YPO_(4)∶Er^(3+),Yb^(3+)上转换发光粉。X射线衍射(XRD)结果表明:所有的样品均为四方结构的YPO_(4)相。PEG对样品的晶粒尺寸有影响。扫描电镜(SEM)结果表明:PEG的加入提高了颗粒的分散性和均匀性。红外光谱分析结果表明:PEG的添加对发光粉结构没有明显的影响。980nm红外光激发下,YPO_(4)∶Er^(3+),Yb^(3+)发光粉的上转换发射光谱显示出来自Er^(3+)离子绿光和红光的特征发射。各样品的发光强度和红光/绿光相对强度比与晶粒尺寸、晶粒表面形貌有关。讨论了可能的上转换发光过程,并计算了样品的色坐标。 展开更多
关键词 YPO_(4) 上转换发光 共沉淀法 聚乙二醇
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Modification of MgO-CaO Clinkers for Hydration Resistance
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作者 SHE Aixin LI Ningbo +2 位作者 HUANG Ren HUANG Zhong ZHANG Haijun 《China's Refractories》 2025年第1期12-17,共6页
Mgo-Cao refractories are widely used in the iron and steel metalurgy industry due to their advantages of purifying molten steel,high refractoriness,good thermal shock resistance,and excellent corrosion resistance to b... Mgo-Cao refractories are widely used in the iron and steel metalurgy industry due to their advantages of purifying molten steel,high refractoriness,good thermal shock resistance,and excellent corrosion resistance to basic slags.However,hydration occurs during the manufacturing,storage,and transportation of refractories,which severely limits their application.Mgo-CaO clinker is the main raw material for Mgo-Cao refractories,and its hydration resistance determines the development of the latter case.Herein,the Mgo-Cao clinker was modified using myristic acid as the modifying agent by the liquid-phase deposition method.The effects of the particle size of the raw materials,concentration of myristic acid,treatment temperature and time on the phase composition and hydration resistance of the modified Mgo-Cao clinkers were investigated in detail.The results show that the samples with an agent concentration of 0.25 mol L^(-1) and treated at 25℃ for 1 h exhibit the optimal hydration resistance properties,namely a low hydration mass gain rate(0.23%)and a large water contact angle(152.9). 展开更多
关键词 Mgo-Cao clinkers surface modification liquid-phase deposition method hydration resistance
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配锂量对LiNi_(0.9)0Mn_(0.07)Al_(0.03)O_(2)正极材料电化学性能影响的研究
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作者 申琦荣欣 艾登登 +2 位作者 金生萍 席儒恒 后小毅 《无机盐工业》 北大核心 2025年第7期50-56,共7页
随着现代社会对电池能量密度需求的日益增长,研究者的关注重点放到了高比容量的高镍层状正极材料上,但高镍材料的煅烧条件十分苛刻,材料合成复杂,因此需要探究其合成条件。采用共沉淀法成功制备了3种不同配锂量(1.02、1.04、1.06)的LiNi... 随着现代社会对电池能量密度需求的日益增长,研究者的关注重点放到了高比容量的高镍层状正极材料上,但高镍材料的煅烧条件十分苛刻,材料合成复杂,因此需要探究其合成条件。采用共沉淀法成功制备了3种不同配锂量(1.02、1.04、1.06)的LiNi_(0.9)0Mn_(0.07)Al_(0.03)O_(2)(NMA973)正极材料,探究了不同配锂量对正极材料NMA973的结构形貌、电化学性能的影响。通过XRD、SEM表征得出NMA973-1.04正极材料具有良好的层状结构。通过XPS测试得出NMA973-1.04正极材料的Ni^(3+)含量较高,进一步证明Li^(+)/Ni^(2+)混排程度较低。ICP测试证实了NMA973-1.04正极材料的Li含量是最接近设计值的。电化学测试表明,NMA973-1.04正极材料在不同倍率下都显示出较高的放电比容量,小倍率0.2C的放电比容量可以达到199.00 mA·h/g,从大倍率5.0C再回到小倍率0.2C放电比容量仍为198.60 mA·h/g,容量保持率高达99.0%;在1.0C倍率循环100次后容量保持率为89.0%,这展示了NMA973-1.04正极材料的优异循环性能和结构稳定性。结果说明,配锂量为1.04的NMA973正极材料具有优异的性能。 展开更多
关键词 锂离子电池 高镍三元正极 配锂量 共沉淀法
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基于Al掺杂SnO_(2)纳米线制备透明抗静电压敏胶薄膜
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作者 李晓东 张钰钒 刘左欣 《功能材料》 北大核心 2025年第11期11159-11165,共7页
透明抗静电压敏胶薄膜兼具透明特性与抗静电功能,在多领域展现出显著应用价值。然而,该薄膜存在透明度与抗静电性能难以兼顾、生产工艺复杂、成本高昂、部分成分存污染等问题。SnO_(2)纳米线具有高长径比、低制备成本的优势,是良好的导... 透明抗静电压敏胶薄膜兼具透明特性与抗静电功能,在多领域展现出显著应用价值。然而,该薄膜存在透明度与抗静电性能难以兼顾、生产工艺复杂、成本高昂、部分成分存污染等问题。SnO_(2)纳米线具有高长径比、低制备成本的优势,是良好的导电颗粒的载体。采用共沉淀法制备了高长径比的Al掺杂的SnO_(2)纳米线并采用化学沉积法包覆银。通过涂布工艺在聚对苯二甲酸乙二酯(PET)基材上制备了基于Al-SnO_(2)@AgNWs的薄膜。结果表明,3%浓度的Al掺杂下的长径比(150)最大、镀银后电阻率(0.46 mΩ·cm)最小。薄膜形成了网状的导电通路,导电填料添加量2.5%时表面电阻最小(3.35×10^(5)Ω/sq),可见光透过率可达到75%。 展开更多
关键词 抗静电 透过率 Al掺杂SnO_(2)纳米线 共沉淀法 化学沉积镀银
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煅烧温度对高镍无钴LiNi_(0.9)Mn_(0.1)O_(2)正极材料结构与电化学性能的影响
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作者 胡雷雷 吴昊哲 +4 位作者 张一博 赵亮 吴熹 贺英 后小毅 《化工新型材料》 北大核心 2025年第S1期167-172,共6页
高镍无钴LiNi_(0.9)Mn_(0.1)O_(2)被认为是目前具有潜力的锂离子电池正极材料之一。通过有机胺共沉淀和高温固相法制备了高镍无钴LiNi_(0.9)Mn_(0.1)O_(2)(NM91)二元正极材料,并通过结构表征和电化学性能测试探究煅烧温度对正极材料结... 高镍无钴LiNi_(0.9)Mn_(0.1)O_(2)被认为是目前具有潜力的锂离子电池正极材料之一。通过有机胺共沉淀和高温固相法制备了高镍无钴LiNi_(0.9)Mn_(0.1)O_(2)(NM91)二元正极材料,并通过结构表征和电化学性能测试探究煅烧温度对正极材料结构和电化学性能的影响。通过X射线衍射(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)和电化学性能对NM91正极材料外貌和结构进行分析,结果表明:在750℃时NM91正极材料的阳离子混排低,I_((003))/I_((104))比值最高,形貌趋于完整。同时电化学性能最佳,在0.1C下首次充放电库仑效率可达85.04%,0.5C下循环100圈后容量保持率为87.18%,1.0C下循环100圈后容量保持率为70.81%。H2-H3有害相变降低,显著提高了富镍阴极材料的结构稳定性,从而提高了富镍二元锂离子电池的电化学性能。 展开更多
关键词 锂离子电池 正极材料 高镍LiNi_(0.9)Mn_(0.1)O_(2) 有机胺共沉淀法
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Ti掺杂协同AlPO_(4)包覆的富锂锰基正极材料
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作者 魏远航 董溱 +1 位作者 贾雨 屈龙 《电池》 北大核心 2025年第6期1277-1284,共8页
富锂锰基正极材料具有能量密度高、功率密度高和生产成本低等特点。采用共沉淀法合成Ti掺杂过渡金属碳酸盐前驱体,再由固相法制备Ti掺杂协同AlPO_(4)包覆的富锂锰基正极材料LMNC-Ti@AlPO_(4)。利用XRD、SEM、透射电子显微镜(TEM)、电感... 富锂锰基正极材料具有能量密度高、功率密度高和生产成本低等特点。采用共沉淀法合成Ti掺杂过渡金属碳酸盐前驱体,再由固相法制备Ti掺杂协同AlPO_(4)包覆的富锂锰基正极材料LMNC-Ti@AlPO_(4)。利用XRD、SEM、透射电子显微镜(TEM)、电感耦合等离子体发射谱(ICP-OES)和X射线光电子能谱(XPS)等技术,对样品进行分析。LMNC-Ti@AlPO_(4)具有六方晶系R-3m点群和单斜晶系C2/m点群的复合结构,呈现类球形形貌,锰元素在材料表面呈Mn^(3+)和Mn^(4+)混合分布的特点。Ti掺杂协同AlPO_(4)包覆,可提升电化学性能。LMNC-Ti@AlPO_(4)在2.0~4.6 V充放电,0.1 C倍率下的首次库仑效率提升至93.4%;1.0 C倍率下的首次放电比容量为242.8 mAh/g,70次循环后,容量保持率提升至90.1%。 展开更多
关键词 锂离子电池 正极材料 富锂锰基材料 固相法 共沉淀技术 Ti掺杂 AlPO_(4)包覆
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