乙醇钽化学气相沉积制备Ta2O5薄膜研究进展

Ta2O5薄膜层具有较高的介电常数、折射率以及和ULSI加工过程中的相容性，因而将在硅芯片栅层材料、动态随机存储器、减反膜、气敏传感器、太阳能光伏电池面板介电层等方面得到应用。对以Ta（OC2H5）5为原料，通过常规金属有机化合物气相沉积、光致化学气相沉积、等离子增强化学气相沉积、原子层化学气相沉积和脉冲化学气相沉积法制备Ta2O5薄膜进行了评述，并对这些方法存在的问题进行了分析。     

电化学直接合成已醇铌研究

采用电化学方法用金属铌直接合成了乙醇铌,用拉曼光谱,红外光谱和元素分析对产品进行了表征。结果表明:乙醇含水量对槽电压及阳极的溶解行为有显著的影响:随着含水量的增加,恒流电解所需的起始电压迅速增大,且电解过程中槽电压升高的速度和幅度越大。在经除水处理的乙醇中,铌阳极呈现层片状的均匀腐蚀,这种特征不随槽电压和电解时间的变化而改变;在未经除水的乙醇中,槽电压低时,阳极呈现点蚀的特点,槽电压高时,阳极腐蚀呈现均匀腐蚀。研究表明:电化学合成乙醇铌的关键是要设法除去乙醇中少量的水分。     

铱钽涂层钛阳极的制备工艺研究

本文参考了大量的有关文献,结合部分实验,从制备工艺角度较详细地总结了近年来国内外对铱钽涂层析氧金属阳极的研究情况,分析了制备过程中工艺参数的选择问题。其中包括铱钽涂层的制备方法、涂液配制、烧结温度和贵金属被覆量等。     

钽的氮离子注入法研究

实验研究证实,通过氮离子注入的方法对钽基材进行表面强化,可大大提高钽材的表层硬度及耐蚀性能。俄歇电子能谱及X射线衍射分析表明,Ta注入N~+后生成了新相TaN_(0.1)。     

Electrochemical synthesis and characterization of tantalum alkoxides

Tantalum(V) propoxide (Ta(OPrⁿ)₅), isopropoxide (Ta(OPrⁱ)₅) and butoxide(Ta(OBuⁿ)₅) were synthesized by electrochemical reactions of corresponding alcohol at sacrificial tantalum anode in the presence of tetraethylammonium chloride as a conductive additive. The pure products were isolated by reduced pressure distillation under 5 kPa. The crystal of Ta(OPrⁱ)₅ was obtained by recrystallization from hexane at ?10 °C. These samples were characterized by Fourier transform infrared spectra (FT-IR), Raman spectra, nuclear magnetic resonance spectra (NMR), TG/DTA and ICP-MS. The results show that direct electrochemical synthesis of metal alkoxides has a high current efficiency and electrolysis yield. These alkoxides have a high purity of 99.97% and can be directly used as the precursor of Ta₂O₅ films.     

阳极氧化钽酸锂薄膜在NaOH溶液中的腐蚀行为研究

通过阳极氧化法在高纯钽片表面制备了钽酸锂复合薄膜,采用浸泡失重法和电化学测试法考察了镀膜前后样品在10% (质量分数) NaOH溶液中的腐蚀行为。利用X射线衍射仪、扫描电子显微镜及能谱仪分别对薄膜的物相组成、表面及截面形貌、膜层厚度进行了测试分析。结果表明,阳极氧化后得到的复合薄膜由钽酸锂和氧化钽组成;该薄膜与基体之间结合良好,厚度约3 μm;镀膜后样品的质量腐蚀速率至少减少了6倍,腐蚀电流密度下降了2个数量级,腐蚀96 h后样品表面没有明显变化。而对比的纯钽样品却发生了严重的腐蚀反应,生成了很多长条状和多棱柱状的腐蚀产物Na₃TaO₄、Na₂Ta₂O₆和Na₈Ta₆O₁₉。     

基于TNTs中间层的钌铱钽氧化物阳极制备及强化寿命研究

目的 通过TNTs(TiO2纳米管阵列)中间层的引入以及涂层成分调控,制备具有优异析氯性能的长寿命金属氧化物阳极.方法 采用阳极氧化法及热处理工艺,在钛基体上原位生长导电性良好、化学性质稳定的TiO2纳米管阵列,进而通过涂覆、热分解法制备不同组成的RuIrTa氧化物复合电极.利用场发射扫描电镜(FESEM)、X射线衍射...     

基于不同碳载体的直接乙醇燃料电池阳极Pt基催化剂的制备及性能表征

本文采用活性炭、介孔碳、碳纳米管和石墨烯为催化剂载体,添加CeO2作为助催化剂,用微波辅助乙二醇还原氯铂酸法制备了五组催化剂。利用X射线衍射仪(XRD)、扫描电镜(SEM)和电子能谱(EDAX)、比表面积及孔径分析仪(BET)及X射线光电子能谱(XPS)等对CeO2及催化剂进行微观结构表征;利用电化学工作站对催化剂进行电化学性能测试。结果表明,以石墨烯为载体并加入CeO2助催化剂合成的催化剂对乙醇的催化氧化具有最佳的活性,稳定性及抗中毒能力,其电化学活性表面积为86.83 m2/g,峰电流密度值为751.03 A/g,且对乙醇催化氧化的活化能最低,1100s时的稳态电流密度值为67.33 A/g。     

基于水下电场测量的Ag/AgCl多孔电极性能研究

以金属钽板为阳极,不锈钢板为阴极,以四丁基溴化铵为导电剂,在二乙胺体系中直接电化学合成5-二乙基胺钽(Ta[N(C2H5)2]5).采用红外光谱(FT-IR)、核磁共振(NMR)、差热分析(TG-DTG.)及等离子质谱(ICP-Mass)对5 kPa 压力下减压蒸馏分离得到Ta[N(C2H5)2]5产品进行了分析检测.分析结果表明得到的产品确实是纯度99.997％的有机胺钽化合物Ta[N(C2H5)2]5.钽阳极溶解机理研究表明,钽阳极在电流的作用下发生点腐蚀,钽阳极在电流及四丁溴化铵的作用下首先生成Ta(NH10C4)n(Br)m,之后Ta(NH10C4)n(Br)m不断被传输到阴极后继续与二乙胺反应,逐步脱去溴离子Br,并最终生成有机胺钽盐Ta[N(C2H5)2]5.     

网状阴极法在碳钢表面沉积氮化钽薄膜的研究

介绍了一种在钢铁基体上制备氮化钽薄膜的新方法———网状阴极法。其设备简单、价格低廉。实验中发现 ,在工艺参数调配合适的条件下 ,可制备出结构为面心立方和密排六方结构的氮化钽薄膜。薄膜较致密且均匀 ,与基体结合良好。分析了优选工艺参数条件下合成的氮化钽膜的成分、组织、表面和断口形貌及结合力。     

Preparation of high-purity tantalum ethoxide by vacuum distillation

Effects of reflux ratio, water addition and content of water in ethanol on the purity and yield of tantalum ethoxide during vacuum distillation were investigated under the operational conditions of pressure of 1kPa, oil bath temperature of 210-230 ℃, and outlet temperature of 190℃. The condensate sample was characterized by FTIR, 1↑H-NMR spectroscopy and Raman spectra, respectively. The contents of tantalum, carbon and hydrogen in the sample were also determined with elemental analysis instrument. The obtained results consistently demonstrate that the condensate is tantalum ethoxide. The content of impurity, such as Al, As, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sn, Ti, V and Zn, in tantalum ethoxide is less than 0.000 05%, while Nb content is less than 0.000 5%. The content of impurities in tantalum ethoxide sample excels that of Epichem Group＇s requirement for Ta（OC2H5）5 of 99.999%.     

高纯纳米氧化钽的制备

以自制高纯乙醇钽为原料，通过水解、干燥与煅烧生产粒度约35nm的高纯Ta2O5纳米粉。研究了水解过程中乙醇钽浓度、温度、加料时间对产品粒度的影响以及煅烧温度与时间对Ta2O5晶形的影响。选取水解最佳条件为：乙醇钽浓度1.0mol／L，水解温度50℃左右，加料时间约15min。加完后，搅拌5min，接着加入氨水溶液调节pH值到8～9，同时升温至80℃-85℃保温30min；煅烧温度800℃，时间2h。得到的Ta2O5产品粒度约35nm，纯度〉99．997％。     

Electrochemical behavior of tantalum in ethylene carbonate and aluminum chloride solvate ionic liquid

To investigate the electrochemical reduction mechanism of Ta(V) in ethylene carbonate and aluminum chloride (EC−AlCl₃) solvate ionic liquid, cyclic voltammetry experiments were conducted on a tungsten working electrode. Four reduction peaks were observed in the cyclic voltammogram of the EC−AlCl₃−TaCl₅ ionic liquid. The reduction peaks at −0.55, −0.72, and −1.12 V (vs Al) were related to the reduction of Ta(V) to tantalum metal by three stages including the formation of Ta(IV) and Ta(III) complex ions. The reduction of Ta(III) to tantalum metal was an irreversible diffusion-controlled reaction with a diffusion coefficient of 3.7×10⁻⁷ cm²/s at 323 K, and the diffusion activation energy was 77 kJ/mol. Moreover, the cathode products at 323 K were characterized by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. The results showed that tantalum metal and tantalum oxides were obtained by potentiostatic electrodeposition at −0.8 V for 2 h.     

钽在硫酸氢根离子无水乙醇溶液中的电化学行为

采用动电位极化、循环伏安、电流暂态和阻抗等技术研究钽在四丁基硫酸氢铵（TBAHS）乙醇溶液中的电化学行为。研究结果表明：循环伏安曲线中没有活化-钝化转变,阳极电流密度随溶液温度、TBAHS浓度、电位扫描速率和水含量增加而增加;表观活化能为43.389kJ/mol,溶解过程为扩散控制。恒电位测试结果表明,当电位较低时,电流密度逐渐降至一稳定值;当电位高于某一值时,电流密度最初下降至一最小值然后逐渐增加。钝化膜电阻随电位升高而减小,当电位高于2.0V时,出现感抗弧。     

环氧氯丙烷引发的氧化钽气凝胶表征(英文)

介绍了一种以环氧氯丙烷为凝胶促进剂,乙醇为溶剂的块状氧化钽气凝胶的合成工艺及气凝胶样品表征。氧化钽气凝胶的微观显微结构分别由场发射扫描电子显微镜(FESEM),高分辨透射电镜(HRTEM)给出,其孔结构及其分布由等温N2吸附实验给出。结果表明,气凝胶的骨架主要由粒径约1.5nm的初级颗粒构成,等温吸附结构表明,气凝胶主要是由微孔和中孔构成的BET比表面积为835m2/g气凝胶样品。     

三种铝合金阳极的电化学性能对比

通过测试三种铝阳极的电化学效率、电位以及交流阻抗与极化曲线,对三种铝阳极进行了优选.     

铝表面聚苯胺的电化学合成与性能研究

目的 提高铝在含氯离子介质中的耐腐蚀性能.方法 在含有0.4 mol/L苯胺的1 mol/L硫酸中,采用恒电位法和循环伏安法在铝表面电化学合成聚苯胺,用红外光谱、紫外光谱和扫描电镜对聚苯胺的结构和形貌进行表征.通过动电位极化曲线和电化学交流阻抗测试,研究聚苯胺在0.6 mol/L NaCl、0.6 mol/L HCl、0.3 mol/L H2 SO4和0.3 mol/L H2 SO4+0.6 mol/L NaCl几种腐蚀介质中对铝的防护性能.结果 红外光谱表明,合成的是硫酸掺杂态聚苯胺.紫外-可见光谱表明,不同电化学方法 合成的聚苯胺吸收峰位置相近.扫描电镜观察显示,恒电位法制备的聚苯胺为纳米短棒状结构,而循环伏安法制备的聚苯胺呈现出颗粒状结构.聚苯胺涂层铝在各种腐蚀溶液中的自腐蚀电位都比铝正移,在0.3 mol/L H2 SO4中,恒电位法和循环伏安法制备的试样自腐蚀电位分别提高了769、894 mV.相比于恒电位法,循环伏安法制备的聚苯胺涂层具有更好的防腐蚀性能,在0.3 mol/L H2 SO4+0.6 mol/L NaCl中的保护效率高达91.69%,在0.6 mol/L HCl和0.6 mol/L NaCl溶液中的保护效率分别为80.40%和6.54%.结论 聚苯胺涂层在酸性溶液中比在中性溶液中具有更明显的腐蚀防护效果,在0.3 mol/L H2 SO4+0.6 mol/L NaCl强腐蚀性溶液中能对铝基体起到良好的防腐蚀作用.     

Characteristics of Tantalum Surface Treated by 6-Triethoxysilylpropylamino-1,3,5-Triazine-2,4-Dithiol Using XPS

The characteristic of material surfaces has a vital status in its application,for instance,surface properties of materials play a decisive role in adhesion technology between different materials.A method called molecule adhesion technology which can successfully adhere different materials such as polymers,rubbers,metals and exhibit strong adhesion strength without any adhesive agents.In this work,the rare metal of tantalum surface treated by corona and a molecular adhesive(6-triethoxysilylpropylamino1,3,5-triazine-2,4-dithiols,TES)has been investigated to clarify the reaction mechanism between tantalum and TES.Chemical structures of surfaces treated by corona and TES were also analyzed.TES contains two functional groups:one is alkoxysilyl group which can react with the OH group linked tantalum formed by the corona discharge treatment;the other is dithiol triazinyl group reacted with many other materials.Blank tantalum,corona treated and TES treated surfaces situation were analyzed by X-ray photoelectron spectroscopy(XPS).The result shows that the functional structure of OH groups was formed after corona discharge process and TES can be successfully reacted on the tantalum surface.This research can be as a preparation work to achieve the tantalum and other materials adhesion by using molecule adhesion technology in the MEMS and NEMS electronic device fields.