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| 昆明贵金属研究所->《贵金属》杂志-> 2006年第2期摘要 |
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《贵金属》2006年第2期（总104期）摘要 1，纳米银粉的制备及表征 魏智强1,2, 夏天东2，冯旺军1，王 青1, 戴剑锋1 ，闫鹏勋3(1. 兰州理工大学 理学院，甘肃 兰州 730050；2. 兰州理工大学 甘肃省有色金属新材料国家重点实验室，甘肃 兰州 730050；3. 兰州大学 物理科学与技术学院，甘肃 兰州 730000 ) Preparation and Characterization of Silver Nanopowders Abstract: Silver nanopowders were synthesized by chemical reduction method at room temperature. The product was characterized by x-ray diffraction (XRD), transmission electron microscopy(TEM), FT-IR spectrum, thermogravimetric analysis(TGA)and differential scanning calorimetry(DSC). The experimental results showed that the Ag nanoparticles are in high dispersion state with uniformly quasi-spherical shapes, the average particle size is about 26nm with a narrow size distribution ranging from 10nm to 50nm. It is also found that the crystal structure of the Ag nanopowders is the same as the bulk materials, namely fcc structure and that the nanopowders have strong adsorption property. 摘 要: 采用化学还原法制备了纳米Ag粉，并通过X射线衍射(XRD)、透射电子显微镜(TEM)、红外吸收光谱(FT-IR)、热失重分析(TGA)和差示扫描量热分析(DSC)等测试手段对样品进行性能表征。结果表明：在所选择的实验条件下制备了类球形分布、分散性好的Ag纳米颗粒，其粒径主要分布在10～50nm范围，平均粒径为26nm，晶体结构与相应的块体材料基本相同，为fcc结构，具有很强的吸附性。
李贵发，彭 平*，陈 律，胡艳军 ( 湖南大学 材料科学与工程学院，湖南 长沙 410082 ) A First-Principles Calculation of Properties of Ag Free Surfaces LI Guifa, PENG Ping*, CHEN Lü, HU Yanjun( School of Materials Science & Engineering, Hunan University, Changsha, Hunan 410082, China ) Abstract: Using first-principle pseudopotential plane wave method, the energetics, atomic geometries and electronic structures of fcc-Ag crystal and its (111), (110) and (100) surface models were calculated. According to the calculation of surface energy, the structural stability of Ag surfaces, which increases in the following order: Ag(110)＜Ag(100)＜Ag(111), was predicted. And the reason that causes the difference of the structural stability was analyzed in terms of comparison their atomic geometries and electronic structures. It was found that the relaxation of the surface atom layers not only causes the change of geometrical structures of the surface models but also leads to variation of their electronic structures and bonding characters. The relaxation makes a part of valence electrons of the surface layer atoms run into the outer vacuum region above surface layers, which results in the change of peak contour of density of states (DOS) of surface layer atoms and the emergence of some new surface states. The increments of the total energy caused by these change are the main reason of their surface energies. And that the Ag(110) surface having higher activity than that of Ag(111) and Ag(110) surfaces may be attributed to its apparent relaxation of the surface layer atoms. 摘 要：采用第一原理赝势平面波方法，计算了Fcc-Ag晶体及其Ag(111)、Ag (110)与Ag (100)自由表面的能量、几何与电子结构。根据表面能的计算，预测了Ag表面的结构稳定性，结果表明密排Ag (111)面结构稳定性最好，低指数奇异面Ag(100)面次之，Ag(110)面的结构稳定性最差。通过对不同表面几何与电子结构的比较，初步分析了其结构稳定性差异的产生原因。表面原子驰豫不仅引起表面几何结构的变化，而且使表面层的电子结构与键合特性发生改变。驰豫后表面层原子的部分价电子跑到了表面层以上的真空区，使表面层原子的电子态密度峰形发生变化，还新形成了表面态，这是表面能产生的主要原因，而Ag(110)表面相对于Ag(111)与Ag(110)表面具有高表面活性的主要原因则源于其表面层原子显著的结构驰豫。
陈为亮1，闫建英1，宋 宁1，李秋霞2，杨 斌1，戴永年1（1. 昆明理工大学 真空冶金国家工程实验室，云南 昆明 650093；2. 云南师范大学 化学化工学院，云南 昆明 650092） Study on Silver Nanopowder Prepared by Chemical Reduction with an Organic Reductant CHEN Weiliang1, YAN Jianying1, SONG Ning1, LI Qiuxia2, YANG Bin1, DAI Yongnian1( 1. National Engineering Laboratory of Vacuum Metallurgy, Kunming University of Science and Technology, Kunming, Yunnan 650093, China; 2. Faculty of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming, Yunnan 650092, China ) Abstract: Based on the chemical reduction method of organic reductant BSG, the influence of some factors, such as the surfactant and its dosage, the concentration of Ag+, the reaction temperature, on the particle size of silver nanopowder under alkaline condition, was investigated. When PVA was used as the surfactant, silver nanopowder with particle size of less than 100nm were prepared under following condition of 25～50℃, Ag+ concentration of 0.1～0.5mol/L and high speed stiring. 摘 要：采用化学还原法制备纳米银粉，研究了以有机试剂BSG为还原剂，碱性条件下表面活性剂的种类和用量、银离子浓度以及反应温度对所生成银粉粒径的影响。以PVA为表面活性剂，在反应温度为25～50℃、[Ag+]为0.1～0.5mol/L和高速搅拌的条件下，制备出了平均粒径小于100nm的银粉。
赵 明，龚茂初，蔡 黎，张怀红，张丽娟，毛小波，陈耀强*（ 四川大学 化学学院催化材料研究所， 四川 成都 610064 ） Performance of Advanced Rare Earth Oxygen Storage Materials and Application in Three-way Catalysts ZHAO Ming, GONG Maochu, CAI Li, ZHANG Huaihong, ZHANG Lijuan, MAO Xiaobo, CHEN Yaoqiang* ( College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China ) Abstract：CeO2-ZrO2-Y2O3(CZ-Y) and CeO2-ZrO2(CZ)composite oxides were prepared by coprecipitation technique, TPD, BET and oxygen storage capacity(OSC）investigations were carried out on samples. The influence of the composite oxides on the catalytic activity of Pt-Rh three-way catalysts was investigated. The results showed that the catalysts containing CZ-Y soild solutions have high activity and high thermostability compared with that containing CZ solid solution. 摘 要：采用共沉淀法制备了铈锆复合氧化物CeO2-ZrO2-Y2O3(CZ-Y)和CeO2-ZrO2(CZ)，对其进行了BET、TPD和储氧量(OSC)的表征，并考察了这两种铈锆复合氧化物对Pt-Rh型三效催化剂性能的影响。结果表明，含CZ-Y的催化剂具有较好的低温活性和抗老化性能。
江珍雅, 陈敬超（昆明理工大学 云南省新材料制备与加工重点实验室，云南 昆明 650093） Nonparabolic Rate Law of Internal Oxidation Process for AgSn Alloy Powders JIANG Zhenya, CHEN Jingchao ( Key Lab. of Advanced Materials of Yunnan
Province, Kunming University of Abstract: Using the method of progressive oxidation weight gain, the kinetic behavior of internal oxidation of AgSn alloy powders at moderate and low temperature range was investigated. The kinetic curves of internal oxidation for AgSn alloy powders in our study are quite different from the parabolic law showed in Wagner’s model. The internal oxidation mechanisms in different stages for moderate and low temperature internal oxidation of AgSn alloy powders accord with different laws. The control link for kinetic behavior of internal oxidation of AgSn alloy powders at moderate and low temperature is mutural action of chemical reaction and diffusion of product layers. 摘 要：采用逐步氧化增重法，研究了AgSn合金粉末中低温内氧化的动力学行为，结果表明其内氧化动力学曲线明显不同于高温氧化的抛物线定律，中低温氧化的各个不同阶段的内氧化机制符合不同的规律，区别于高温氧化，本实验合金粉末的中低温内氧化过程动力学由化学反应和产物层扩散相互作用控制。
王爱丽1，殷恒波1*，任 敏1，姜廷顺1，周全法2，蒋银花1，陈康敏1，周卫平3( 1. 江苏大学 化学化工学院，江苏 镇江 212013；2.
江苏技术师范学院 化学化工学院，江苏 常州 213001； Effects of Different Organic Functional Groups on Morphology-controlled Synthesis of Silver Nanoparticles at Room Temperature WANG Aili1, YIN Hengbo1*, REN Min1, JIANG Tingshun1, ZHOU Quanfa2, JIANG Yinhua1, CHEN Kangmin1, ZHOU Weiping 3( 1. Faculty of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2. Department of Chemical Engineering, Jiangsu Teachers University of Technology, Changzhou, Jiangsu 213001, China; 3. Faculty of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China ) Abstract: Silver nanoparticles with average particle size ranging from 2 to 131nm were manipulatively synthesized starting from silver nitrate using 10 kinds of different functional group-containing organic modifiers, such as polyvinylpyrrolidone, tween-80, sodium dodecyl sulfate, sodium polyacrylate, polyethylene glycol, D-sorbitol, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, polyvinyl alcohol, cetyltrimethylammonium bromide, at room temperature. The effects of the organic modifiers on the morphology of resulting silver nanoparticles were strongly dependent on the intrinsic properties of the functional groups and the reducibility of reductants. Numerous ether bonds (–O–) presented in polyethylene glycol and tween-80 were beneficial to the formation of silver nanoparticles with particle sizes of several nanometers in a narrow size distribution in both weak and strong reducing environments. Cetyltrimethylammonium bromide induced to form the nanosized silver triangle plates in a weak reducing environment, and to form the grained silver powders in a strong reducing condition. The crystal growth of the silver nanoparticles with particle sizes of more than 10nm was postulated through an adhesion process of small sized ones followed by a subsequent coalescence process under the present reaction conditions. 摘 要：选择10种含有不同官能团的有机物为表面修饰剂，如聚乙烯吡咯烷酮、吐温-80、十二烷基硫酸钠、聚丙烯酸钠、聚乙二醇、山梨醇、十二烷基磺酸钠、聚乙烯醇、十二烷基苯磺酸钠和十六烷基三甲基溴化铵等，在室温下进行了平均粒径在2～131nm范围内纳米银颗粒的控制合成研究。有机修饰剂中含有的不同官能团对制得的纳米银形貌的影响主要取决于有机修饰剂的官能团特性和还原剂的还原能力。在不同还原条件下，含多醚键的聚乙二醇、吐温-80皆易于合成出平均粒径为几纳米、粒径分布窄、分散性好的纳米银。在弱还原剂条件下，十六烷基三甲基溴化铵诱导生成了三角形片状纳米银，但是在强还原剂存在条件下生成了粒状纳米银。粒径大于10nm的纳米银晶体的生长是通过小颗粒的聚集与熔合而成，而不是经过小颗粒的溶解-沉积过程形成。
汪云华，关晓伟，陆跃华（贵研铂业股份有限公司，云南 昆明 650221） Separation of Trace Rhodium from Iridium Solution by Hydrogen WANG Yunhua, GUAN Xiaowei, LU Yuehua ( Sino-Platinum Co. Ltd., Kunming, Yunnan 650221, China ) Abstract: The method of selective reduction of rhodium by normal pressure hydrogen to seperate trace rhodium from iridium solution was studied. The effects of temperature, hydrogen flow rate，reaction time, initial rhodium concentration and concentration of HCl were investigated. Under a certain condition, the rhodium concentration in the residual solution is 0.0007g/L, the change of concentration of iridium is little in the experimental condition. 摘 要：研究了常压氢还原法分离铱溶液中微量铑的方法，并考察了温度、氢气流量、反应时间、铑的初始浓度和溶液中的盐酸浓度等因素对选择性还原铑的影响。研究结果表明在一定条件下，氢还原可使实际铱溶液中铑降到0.0007g/L，而铱基本上不会被还原。
付慧静，傅立新，李俊华* ( 清华大学 环境科学与工程系, 北京 100084 ) Influence of Ceria-Zirconia Solid Solution on Performance of Noble Metal Monolithic Oxidation Catalyst
Abstract: CeXZr1-XO2 solid solution was prepared by co-precipitation method, while powder and monolith honeycomb catalysts were prepared by impregnating carriers with certain CeXZr1-XO2 aqueous solution. The crystalline structures of CeXZr1-XO2 and Ce0.5Zr0.5O2/Al2O3 were characterized by XRD, and the adsorbability was examined by TPD-C3H6. The results showed that the solid solution was obtained in CeO2-ZrO2 composite oxides, the addition of CeO2-ZrO2 to γ-Al2O3 improved the adsorptive power of CeXZr1-XO2/ Al2O3 to C3H6. The behavior of these catalysts was examined by propene oxidation in a fixed-bed microreactor under excess oxygen. It was found that when the adding amount of CeXZr1-XO2 was equal, Pt/Ce0.6Zr0.4O2/Al2O3/cordierite showed the best activity, which was still lower than that of Pt/Al2O3/cordierite. So the addition of ceria-zirconia solid solution restrained the catalytic activity in the presence of excessive oxygen, when the amount of noble metal such as platinum was quite low. The more the ceria-zirconia solid solution was loaded, the worse was the performance of the catalysts as oxidative catalyst. 摘 要：采用共沉淀法制备了不同铈锆比的粉末铈锆固溶体，考察了铈锆比和铈锆固溶体负载量对浸渍法制备的颗粒状和整体样贵金属催化剂上C3H6(丙烯)氧化反应催化性能的影响，并运用XRD和TPD表征技术对催化剂的物化性能进行研究。结果表明，所制备的催化剂中均形成了铈锆固溶体，并且铈锆含量的增加能够提高催化剂对C3H6的吸附能力。当铈锆固溶体的负载量相同时，在氧化气氛和较低贵金属含量条件下、Ce0.6Zr0.4O2的加入使催化剂在低温时具有最好的催化效果。但与Pt/Al2O3相比，采用浸渍法添加铈锆固溶体降低了贵金属整体样催化剂的活性，且活性随着负载量的增加显著降低。
张曙东，雷远进，刘小荣，顾永万，潘再富（昆明贵金属研究所, 云南 昆明 650221） Study on Preparation of Pd/C Catalyst with Palladium(Ⅱ) Acetylacetonate as Precursor ZHANG Shudong, LEI Yuanjin, LIU Xiaorong, GU Yongwan, PAN Zaifu( Kunming Institute of Precious Metals, Kunming, Yunnan 650221, China ) Abstract: A series of activated charcoal supported palladium catalysts was prepared by the impregnation-reduction method with Pd(acac)2 , PdCl2 and Pd(NO3)2 as precursors, respectively. The resin disproportionation was used to evaluate the catalytic activity. The effect of the type of activated charcoal, pretreatment of the support, solvent, reduction method and temperature on the catalytic activity of Pd/C were studied. The results showed that using activated charcoal with large specific area and pore capacity as the support is beneficial to homogeneous distribution of Pd particles on the surface, thus to promotion of catalytic activity; using Pd(acac)2 as precursor, and the solvent with strong polarity may raise catalytic activity of Pd/C compared with inorganic chemical precursors. And TG-DTA indicated that Pd(acac)2 could be completely decomposed at 350℃. Based on the results, by the method of hydrogen dry-reduction, the authors manufactured the Pd/C catalyst, the performance of which could be comparable to the similar product imported from Japan. 摘 要：分别采用乙酰丙酮钯、氯化钯和硝酸钯作前驱物，用浸渍-还原法制备了一系列Pd/C催化剂，以松香歧化反应评价其活性，研究了活性炭类型、载体预处理、溶剂、还原方法及温度等因素对Pd/C催化剂活性的影响。结果表明，采用具有较大比表面积和孔容的活性炭作载体有利于钯在其表面的均匀分布和催化剂活性的提高；以Pd(acac)2作前驱体，以及使用极性较强的溶剂与用无机配合物前驱体相比，制备的Pd/C催化剂活性较高；TG-DTA分析表明Pd(acac)2在350℃下完全分解，基于此结果，作者在350℃条件下采用氢气干法还原，制备出活性略高于从日本进口的Pd/C催化剂。
费敬银，梁国正，辛文利, 朱光明，马晓燕 (西北工业大学 理学院应用化学系，陕西 西安710072 ) Environmental Friendly Silver Brush-Plating Technique and Its Application FEI Jingyin, LIANG Guozheng, XIN Wenli, ZHU Guangming, MA Xiaoyan ( Department of Applied Chemistry, Northwestern Polytechnical University, Xi’an, Shanxi 710072, China ) Abstract: A new cyanide-free silver brush-plating solution was developed. It is environmental friendly and could be used for depositing silver onto titanium, stainless steel, aluminum, carbon steel, and copper substrates. The experimental results indicated that the performances of the silver coatings meet standard of GB5270-85. The solution has been successfully applied to the fields of the functional surface treatment (such as lowing electrical contact resistance) and shows the potential of replacing the generally used cyanide silver electrolyte, especially in the case of environmental protection and safe production. 摘 要：用环境友好型无氰电刷镀银技术，对钛、不锈钢、铝、碳钢、铜等基材的大型、特型零件进行表面镀银加工，以降低其接触电阻。镀银液的镀厚能力＞200μm，镀银层高温加热不变色，不起皮。该技术使用方便、安全可靠。
李光俐, 朱武勋, 王应进 (贵研铂业股份有限公司, 云南 昆明 650221) Determination of Zn, Cd in Ag-28Cu Alloy by Flame Atomic Absorption Spectrometry LI Guangli, ZHU Wuxun ,WANG Yingjin ( Sino Platinum Metals Co. Ltd., Kunming, Yunnan 650221, China ) Abstract: The samples of Ag-28Cu alloy were dissolved in HNO3. Zn, Cd were determined by flame atomic absorption spectrometry after separated Ag with HCl. The factors such as the instrument condition and interference with coexisting elements were tested. The standard recovery rates were from 87.1 % to 101.7% with the relative standard derivation of 3.5%～6.2%. The method is accurate, simple and rapid. 摘 要：将银铜合金试样经硝酸溶解，加盐酸分离银，采用火焰原子吸收光谱法测定合金中的锌、镉。对仪器条件及共存元素干扰进行了实验，加标回收率在87.1%～101.7%之间，相对标准偏差在3.5%～6.2%之间，方法具有准确、简便、快速等优点。 12, 5-H-酸偶氮若丹宁光度法测定铂的研究 乔 英1，董学畅1*，杨光宇2，朱利亚3，韩 勇1( 1. 云南民族大学 化学与生物技术学院，云南 昆明 650031；2. 云南省烟草科学研究院，云南 昆明 650106; 3. 昆明贵金属研究所，云南 昆明 650221） Study on Spectrophotometric Determination of Platinum with 5-(H-acidazo)-Rhodanine QIAO Ying1, DONG Xuechang1*, YANG Guangyu2, ZHU Liya3, HAN Yong1( 1. School of Chemistry and Biology technology, Yunnan University for Nationalities, Kunming, Yunnan 650031, China; 2. Yunnan Academy of Tobacco Science, Kunming,Yunnan 650106, China; 3. Kunming Institute of Precious Metals, Kunming, Yunnan 650221, China ) Abstract: The color reaction of platinum with 5-(H-acidazo)-rhodanine(HAR) was studied. In the presence of hydrochloric acid solution, HAR can react with platinum to form a stable 2∶1 complex. The molar absorptivity is 1.06×105 L?mol-1?cm-1 at 540nm. Beer’s law is obeyed in the range of 0～30?g/25mL. This method can be applied to the determination of platinum in catalysts with good results. 摘 要: 研究了5-H-酸偶氮若丹宁(HAR)与Pt(IV)的显色反应，在HCl介质中，HAR与Pt(IV)反应生成2∶1稳定配合物，λmax＝540nm，ε＝1.06×105L?mol-1?cm-1。铂含量在0～30?g/25mL内符合比尔定律，新方法用于催化剂中铂含量的测定，结果令人满意。
何 俊1，陈 英2，李雪辉1，马玉刚2，陈小平2，王乐夫1,2( 1. 华南理工大学 化工学院，广东 广州 510640; 2. 茂名学院， 广东 茂名 525000 ) A Review on Development of De-NOX Storage-Reduction Catalysts HE Jun1, CHEN Ying2, LI Xuehui1, MA Yugang2, CHEN Xiaoping2, WANG Lefu1,2 ( 1. School of Chemical Engineering and Energy, South China University Technology, Guangzhou, Guangdong 510640, China; 2. Maoming College, Maoming, Guangdong 525000, China ) Abstract: Mechanisms of de-NOX storage-reduction catalysis, which were studied widely in recent years were introduced. The reasons for de-activation and problems that should be solved were analyzed. The ways of resistance to SO2 poisoning were brought out according to the effect of SO2 on NSR catalysts. The developing direction of NSR catalysts in the near future was also pointed out. 摘 要：本文介绍了NOX储存-还原(NSR)机理，综述分析了催化剂失活的原因和需解决的问题，根据SO2对催化剂的影响，提出了抗硫的方法，指出了今后NSR催化剂的发展方向。
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