过渡金属取代磷钼酸修饰铂电极的电化学行为

在证实了磷钼酸修饰铂电极对甲醇氧化具有较高活性的基础上，合成了3种过渡金属取代的磷钼酸，通过红外光谱测试仍为Keggin结构，并制备了过渡金属取代磷钼酸修饰铂电极，研究了修饰铂电极在硫酸溶液中的电化学行为及对甲醇的催化氧化作用。研究结果表明，3种过渡金属取代的磷钼酸修饰铂电极均对甲醇氧化表现出较高的催化活性，其中锰取代的磷钼酸修饰电极对甲醇的催化活性最高。     

AC5型交流阻抗测试系统的建立

本文介绍了作者研制的AC5型电化学交流阻抗测试系统，它的硬件和软件是针对电化学体系而设计的，因而比一般通用型测试系统操作使用方便。AC5型电化学交流阻抗测试系统可用于金属耐蚀性能、缓蚀剂性能和电池等的研究。     

碳载铂纳米微粒修饰的玻碳电极对甲醇的电催化氧化

利用X射线粉末衍射、透射电镜和扫描电镜对商用Pt/C催化剂反应前后的变化进行了物化表征，同时应用电化学方法研究了甲醇在碳载铂纳米微粒修饰的玻碳电极上的电催化氧化性能。结果表明，修饰电极对甲醇氧化呈现较高的电催化活性。铂氧化物的电化学还原在Pt/c催化剂中受到了抑制，该现象可能是由于Pt与载体碳间的强烈作用所引起的。通过扫描电镜和循环伏安研究表明，该催化剂对甲醇的氧化可能存在着表面结构敏感效应。     

金属的腐蚀与防护

金属腐蚀，是金属和周围介质接触时由于发生化学和电化学作用而引起的破坏作用。从热力学观点看，除了少数贵金属(如金、铂)外，各种金属都有转变成离子的趋势，就是说金属腐蚀是自发的普遍存在的现象。金属被腐蚀后，在外形、色泽以及机械性能方面都将发生变化，造成设备破坏、管道泄漏、产品污染，酿成燃烧或爆炸等恶性事故以及资源和能源的严重浪费，     

Pt和PtBi在H2SO4-CH3OH中的氧还原性能

采用氩弧熔炼后热处理方法制备了PtBi金属间化合物材料.采用循环伏安和旋转圆盘电极手段进行电化学性能测试.通过在0.5 mol/L H2SO4 0.25 mol/L CH3OH溶液中对氧还原的起始电位和电流密度大小比较发现,与光滑铂电极相比,PtBi金属间化合物具有良好的氧还原催化性能和抗甲醇中毒性能.从结构方面分析了PtBi具有抗甲醇中毒性能的原因,认为是PtBi中大的Pt-Pt间距不利于甲醇的吸附解离.X射线光电子能谱(XPS)结果表明,PtBi材料中Pt的d电子空穴增加,可能是导致PtBi电极表面氧还原电流增大的原因.     

海水中阴极保护用镀铂钛阳极的研究

镀铂钛阳极是海水阴极保护中广泛使用的辅助阳极.镀铂钛阳极具有良好的放氯性能,尺寸可变,重量轻,适合海洋中使用.在二亚硝基二氨铂为主盐的酸性镀液中制备了Pt/Ti阳极,测试了Pt/Ti阳极在人造海水中的电化学性能.研制的Pt/Ti电极表面光亮,镀层和基体结合牢固,镀层厚度可达5～10μm,在人造海水中的电化学性能稳定,损耗率为6.0225mg/A.a.     

铂铑合金电化学溶解工艺研究

为解决铂铑合金废料分离提纯工艺中的难题－铂铑合金的溶解，探讨了电化学溶解工艺，论述了在盐酸溶液中加入适量的过氧化氢进行交流电化学溶解的反应机理，讨论了电流密度，盐酸浓度，过氧化氢加入量，温度等因素合金溶解速度的影响，用正交试验方案找出了优化的工艺条件，获得了较快的溶解速度，该法操作简单，不需要赶硝作业，不污染铂铑溶解液，可与王水溶解，中温氯化，熔盐溶解等传统的方法相媲美，不污染的铂铑溶解液，可与王     

离子束溅射制备Pt/C催化电极材料的结构和电化学性能

采用离子束溅射技术制Ｐｔ／Ｃ催化电极,降低了电极耗铂量至０．１９ｍｇ／ｃｍ＾２,电极具有良好的电化学性能。研究了在不同碳质载体材料上用不同沉积条件制备的Ｐｔ／Ｃ电极的电化学性能。     

阴极保护用钛基阳极

阴极保护是防止金属电化学腐蚀的有效方法。在外加电流阴极保护系统中,辅助阳极是个极为重要的组成部分,它的作用是将直流电流通过介质传递到被保护的金属结构上。可以用作辅助阳极的材料有很多,如石墨、铅合金、镀铂钛等。其中镀铂钛是一种较为理想的阳     

电化学方法测试金属涂层的耐蚀性

叙述了电位－时间法，循环伏安法，恒电量方法及交流阻抗波谱法测定金属涂层的耐蚀性，电化学方法快速简便，特别是交流阻抗波谱是评价金属涂层性能和研究其腐蚀行为的最有效方法之一。     

温度对铂钽复合阳极电化学性能的影响

对铂钽复合阳极在200 mA/cm2的电流密度下进行了恒电流试验,通过测量动电位极化曲线以及电化学阻抗谱,研究了阳极在不同温度海水中的电化学行为,利用扫描电镜(SEM)及能谱仪(EDS)对阳极形貌及成分进行了分析。电化学试验结果表明,铂钽复合阳极能承载较大的电流密度;随温度的降低,法拉第电荷传递电阻增大,阳极电化学催化活性有所下降。SEM分析结果表明,阳极表面有微裂纹,阳极工作时表面有大量气体析出,加速了阳极的溶解。     

金核/铂壳纳米粒子的光化学合成及电催化活性

在含不同摩尔比的Au(Ⅲ)和Pt(Ⅳ)离子的PEG(聚乙二醇)-丙酮溶液中,采用光化学共还原法合成了一组Au@Pt复合纳米粒子,并以炭黑分别对其负载制成Au@Pt/C催化剂。借助于UV-Vis、TEM和HR-TEM的表征,证实复合纳米粒子为球形的核/壳结构;分别以XPS、EDS和电化学方法分析了复合粒子的化学状态、结构特点和Au@Pt/C催化剂的催化性质。结果表明,不同Au:Pt摩尔比的Au@Pt/C催化剂对甲醇氧化反应具有良好的催化活性和稳定性,其中Au:Pt=1:1时形成的Au@Pt/C催化剂电催化活性最高,约为商品Pt/C催化剂的4倍。简要讨论了核/壳结构产生高催化活性的主要原因。     

Determination of isothermal section of Ni—Pt—Ta ternary system at 1173K

The isothermal section of the Ni-Pt-Ta ternary system at 1173K was determined by means of the diffusion triple technology and the electron microprobe analysis.The phase relations in this system were studied.Linear compound(Ni,Pt)3Ta with small solubility forming between Ni3Ta and Pt3Ta was identified.Four binary compounds,i.e.Pt2Ta,Ni2Ta,NiTa and NiTa2,and four three-phase fields,i.e.Pt2Ta (Ta) NiTa2,Pt2Ta NiTa2 NiTa,Pt2Ta (Ni,PT)3Ta NiTa and (Ni,Pt)3Ta NiTa Ni2Ta,were also identified.     

多孔生物形态碳/铂颗粒复合材料的电化学行为

利用热解法制备了具有一定生物形态的多孔碳材料,并采用电沉积方法在所得碳材料表面沉积贵金属铂微粒.借助具有良好成膜能力的壳聚糖,把所得到的C-Pt复合材料修饰在玻碳电极表面,运用电化学方法研究了C-Pt复合材料修饰的玻碳电极对过氧化氢的电催化行为.结果发现,铂微粒和碳材料之间的协同作用大大提高了修饰电极的催化性能,对过氧化氢具有良好的电催化活性.     

Electrocatalytic properties of polypyrrole films prepared with platinate(II) counter-ions

Polypyrrole/PtCl₄²⁻ composites were studied with respect to their possible use as a hydrogen electrode, e.g. for fuel cell applications. The impact of composite conditioning on its electrochemical activity for the hydrogen oxidation reaction (HOR) was studied. The cathodic polarization of samples containing a high amount of PtCl₄²⁻ ions after synthesis leads to the formation of polypyrrole/Pt composites active for HOR. Their behavior is, however, different from that of bulk Pt and strongly depends on the potential at which the reduction proceeds. Both electrochemical and IR measurements displayed the self-degradation of composites exposed to cathodic potentials exceeding a certain level. The presence of metallic Pt is proved by means of X-ray photoelectron spectroscopy (XPS) and the extent of platinate ions reduction/motion is discussed. Subsequently the possibility of tuning composite activity by changing the thickness or using a competing counter-ion during synthesis was tested.     

CVD Ta/W复合材料力学性能影响因素的研究

采用室温拉伸实验，扫描电镜，金相显微镜研究了影响CVD法制备的Ta/W层状复合材料力学性能的因素。结果表明：W体积分数，热处理温度，热处理时间均对复合材料的力学性能有较大影响。W体积分数为13%的复合材料同时具有良好的抗拉强度和塑性。能够有效提高复合材料抗拉强度和塑性的热处理制度为1600℃×2h，且热处理主要通过改变复合材料的晶粒大小及界面扩散层厚度来影响材料的力学性能。     

Study on Ti/BDD Film Electrode with Ta Interlayer

Boron doped diamond(BDD)thin films have been deposited on Ti substrate with Ta interlayer by MP-CVD(microwave plasma chemical vapor deposition),and Ta interlayer was deposited by magnetron sputtering.The physical and electrochemical behaviors of the Ti/Ta/BDD electrode and its application in electrochemical oxidation of wastewater containing 2,4-dichlorophenol were studied.Raman spectroscopy and field emission scanning electron microscopy(FESEM)demonstrates that the films obtained exhibit well-defined diamond features.XRD spectroscopy shows no TiC in the BDD film with Ta interlayer.Electrochemical measurement shows the BDD electrode behaves low background current and wide working potential window up to 4 V.Further,the removal efficiency of chemical oxygen demand(COD)of the BDD electrodes were evaluated by the electrochemical oxidation of 2,4-dichlorophenol.     

Electrochemical properties of heat-treated platinized titanium

The physicochemical properties and electrochemical behavior of platinized titanium anodes produced by a combined electrochemical method, which involves electrodeposition of a thin platinum layer on a titanium substrate followed by heat treatment, are studied. The process is shown to result in the appearance of a composite coating with a substantial content of titanium oxides. The composite obtained is an n-type semiconductor, the flat-band potentials of which and the number of charge carriers depend on the preparation conditions. It is proposed to use the reduction peak of oxygen-containing platinum compounds on the stripping voltammogram as a correlation parameter for predicting the electrocatalytic activity of heat-treated Ti/Pt composite electrodes with respect to the oxygen evolution reaction.     

Inter-granular exchange coupling and magnetic anisotropy of Ta/Ru/Co-23 at%Pt perpendicular thin films with different Ru underlayer thicknesses

In the present work, a series of Ta/Ru/Co-23 at%Pt thin films with varied Ru underlayer thicknesses were fabricated by magnetron sputtering. All of the films show c-axis preferred orientation perpendicular to the film surface. The drop of c/a ratio and lattice expansion of Co–Pt layer with the increase in Ru underlayer thickness was revealed by X-ray diffraction(XRD). The coercivity of the Ta/Ru/Co–Pt thin films increases drastically with Ru underlayer thickness increasing, due to the enhancement of effective magneto-crystalline anisotropy constant and exchange decoupling of magnetic nano-grains. The enhancement of effective magneto-crystalline anisotropy constant is ascribed to the lattice deformation of Co–Pt layer by mismatching the Ru layer and Co–Pt surface.Moreover, the exchange decoupling of magnetic nanograins is attributed to the further isolation of magnetic nano-grains.