Pt和Sb、S吸附原子修饰的Pt电极上1,3-丁二醇吸附和氧化过程

应用电化学循环伏安和石英晶体微天平（EQCM）研究了1，3－丁二醇（1，3－BDL）在Pt电极和以Sb,S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的吸附和氧化过程，从电极表面质量变化的结果分析，可认为1，3－丁二醇的氧化与电极表面氧物种有着极其密切的关系。Pt电极表面Sb吸附原子能在较低的电位下吸附氧，可显著提高1，3－丁二醇电催化氧化活性，与Pt电极相比较，饱和吸附Sb原子的Pt电极，1，3－丁二醇氧化的峰电位负移了0．25V，峰电流增加了近1倍，相反，Pt电极表面S吸附原子的氧化会消耗表面氧物种，饱和吸附S原子的Pt电极上1，3－丁二醇的电氧化受到抑制，本文从表面质量变化提供了吸附原子电催化作用的新数据。     

聚苯胺基分散铂电极的电催化行为

为了改善铂基催化剂氧化甲醇的催化活性,采用循环伏安法制备了聚苯胺修饰分散铂电极(Pt-Pan/Pt)、聚苯胺和磷钼酸共同修饰分散铂电极(PMo12-Pt-Pan/Pt).并用循环伏安法研究了制备电极在0.5 mol·L-1H2SO4溶液中的电化学行为以及对甲醇氧化的催化效果.结果表明:PMo12-Pt-Pan/Pt电极对甲醇氧化具有很高的催化活性.PMo12-Pt-Pan/Pt电极对甲醇氧化的最大电流是33.43 mA,是Pt/Pt电极的1.37倍.催化活性的提高来源于聚苯胺和磷钼酸与铂的协同作用.     

铁和钼在LiCl-KCl熔盐中的电化学行为

采用电化学方法研究了S2 -离子在Pt电极上的电极过程机理、铁和钼电极在Li2 S(sat) LiCl KCl和LiCl KCl两种熔融盐体系中的电化学行为 ,铁和钼电极的氧化起始电位差约为 0 .6V .探讨了FeS2 阴极的充电极限电位 ,控制FeS2 阴极的充电电位在钼的钝化区内 ,钼可以用作FeS2 阴极的集流体     

Pt/炭黑改性对石墨电极乙醇电催化的影响

采用真空离子镀和乙醇催化燃烧方法对燃料电池石墨电极进行纳米Pt和炭黑复合表面改性,用扫描电镜(SEM)、透射电镜(TEM)、电化学工作站等手段研究电极表面改性前后的组织形貌和电催化性能,并探讨了纳米Pt和炭黑对电极电催化性能的影响.研究表明,石墨电极经过纳米Pt/炭黑复合表面改性后,其循环伏安曲线上出现了三个氧化峰并具有更大的背景电流.与纳米Pt单一表面改性相比,纳米Pt/炭黑复合表面改性后的电极对乙醇的电催化性更好.纳米炭黑表面改性获得的高比表面积以及催化材料Pt的协同作用有效提高了电极对乙醇的电催化性能.     

爆炸复合Pt/Ti电极的电化学性能

Pt/Ti电极作为一种优良的耐腐蚀复合材料,被广泛应用于海洋工业、氯碱工业及电子工业。根据铂层厚度及性能的差异,电镀与爆炸复合工艺均被广泛应用于Pt/Ti复合电极的工业化生产。采用SEM对爆炸复合Pt/Ti电极的表面及扩散层形貌进行了研究;采用PARSTAT4000型电化学分析仪对爆炸复合Pt/Ti电极试样的极化曲线(Tafel曲线)及循环伏安特性曲线(CV曲线)进行了测试,对比了电镀工艺Pt/Ti电极的电化学性能。结果表明,Pt/Ti复合电极的表面形貌对其电化学活性具有重要影响,爆炸复合工艺制备的Pt/Ti电极表面十分致密,沿着轧制方向具有明显的加工流线,抗腐蚀性能较佳;电镀工艺制备的Pt/Ti复合电极表面铂层呈颗粒状分布,增大了与溶液的实际接触面积,表面活性较好。     

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。     

离子束溅射制备Pt及Pt合金催化电极材料的电化学活性研究

Pt(Pt合金)／C催化电极是燃料电池及电解法制氢的关键部件,提高Pt(Pt合金)／C电极的催化活性一直是研究的热点。本文采用离子束溅射技术(IBS),以石墨纤维布为基底,制备了Pt／C、PtRu／C、PtTi／C和PtNi／C催化电极材料。在2电极电解槽中测试了电极的电化学活性。结果表明,PtRu／C电极比纯铂及其它合金电极具有更好的催化活性。用于间接电解H2S制备H2中试,反应温度从20℃提高到30℃时,电流密度增加约80％;连续运转52lh,电流下降仅2．8％。     

模拟压水堆一回路条件添加Pt技术研究

采用SEM,XPS,XRD和电感耦合等离子体原子发射光谱(ICP-AES)法并结合线性极化曲线研究了模拟压水堆一回路加氢水化学条件下预氧化的316LN不锈钢表面沉积贵金属Pt的方法及其对材料电化学行为的影响。结果表明,预氧化实验中,材料表面形成了双层氧化膜,外层为富Ni层,内层为富Cr层,与反应堆实际运行中材料表面产生的氧化膜结构和成分相似;在模拟热停堆实验条件下,用Na2Pt(OH)6配制含Pt量为0,10,50和100μg·kg-1的溶液能够在316LN材料表面沉积达到目标要求的Pt。电化学实验结果表明,Pt沉积量越多,材料的腐蚀电流密度变化越小,腐蚀电位急剧降低,说明材料抗腐蚀性能提高。     

正交设计法优化掺镧钛基氧化物涂层电极的制备工艺

以RuCl和LaCl为前驱物,通过热分解法制备钛基Ru-La氧化物涂层电极。运用L25(56)的正交试验设计方案,考察了热分解温度、反应时间及La元素掺入量这三个实验因素对Ru-Ti涂层电极表面形貌和电化学性能的影响。结果表明:镧元素的加入不但使涂层表面裂纹细小,而且能够有效增强电极的电化学活性,从而达到延长电极使用寿命、提高电流效率的最终要求。制备钛基Ru-La涂层电极的最佳工艺参数为:温度500℃、时间20 min、La含量1.50%。     

Ti/nano-TiO2-Pt复合电极催化甲醇氧化的研究

采用溶胶-凝胶法(sol-gel)制备纳米TiO2(Ti/nano-TiO2)膜电极,再用电沉积法在纳米TiO2膜上修饰Pt微粒,制成Ti/nano-TiO2-Pt复合电极.用循环伏安法研究了纯Pt丝电极和Ti/nano-TiO2-Pt电极对甲醇氧化的电催化活性以及稳定性.结果表明:对甲醇氧化,复合电极比Pt丝电极具有更高的催化活性,且对甲醇氧化中间产物CO的吸附量少,因而不易中毒;复合电极载铂量达到一定值时,电极具有最强的催化活性.     

消除稳态极化曲线测量中介质电阻影响的一种实验技术

设计了一种新型电解池，配有两支参比电极，参比电极到工作电极之间的距离可精确调节。在进行极化曲线测量时，通过测量工作电极相对于两支参比电极的电位，可求得不同电流密度的下溶液电阻，从而消除溶液电阻的影响。模拟电路和实际体系的测量证明了本实验技术的可行性。     

硅烷偶联剂在镁电极固封中的作用

采用浸涂工艺,用W-78和A-1200硅烷偶联剂对金属镁进行表面处理,然后固封制备成镁电极。对比分析了有和无硅烷偶联剂处理的镁电极的电化学行为。研究表明,两种硅烷偶联剂都可以改善镁电极的性能,显著提高了测试结果的重现性,其中A-1200效果更好。讨论了硅烷偶联剂W-78和A-1200的作用机理。     

溶液电阻对稳态极化曲线测量的影响及一种消除此影响的数据处理方法

如果电极反应过程遵循Ｔａｆｅｌ规律，则在进行稳态极化测量情况下，可以用本文提出的数据处理方法对用等间距恒电位测量或等间距恒电流测量的极化数据进行处理，求得参考电极至工作电极之间的溶液电阻和Ｔａｆｅｌ斜率的数值，从而得到消除了溶液电阻欧姆电位降的真实极化曲线．计算机模拟结果和实验结果都证明，即使在溶液电阻并不大的介质中，如果腐蚀电流密度比较大，溶液电阻对于极化测量的影响也不可忽视．     

A study of the electropolymerization of thiophene

The electropolymerization of thiophene has been studied with cyclic voltammograms using both the conventional type of electrodes and the rotating ring-disk electrode (RRDE). The polymerization process has been examined under various conditions of electrolytic solution as well as with different kinds of working electrodes. Soluble oxidized oligomeric intermediates have been detected in the RRDE measurements during the growing process of the polymer chain, which suggests that these species participate in the polymerization mechanism.     

混凝土结构中钢筋腐蚀电位与腐蚀电流在液面附近的分布

将含钢筋的混凝土试样部分浸泡在3.5% NaCl溶液中,测量溶液以及溶液上方混凝土中钢筋试样的腐蚀电位、宏电池腐蚀电流,通过极化电阻R_p值计算钢筋的腐蚀电流密度。结果表明位于溶液中混凝土内钢筋试样的腐蚀电流密度随着其在溶液中深度的增加而降低。位于溶液上方混凝土中钢筋试样的腐蚀电流密度随着其所处的位置升高而降低,说明溶液中混凝土中钢筋的腐蚀与氧含量密切相关。溶液上方的混凝土中钢筋的腐蚀与混凝土湿度密切相关。     

Effects of sputtering conditions on electrochemical behavior and physical properties of Ni-Mo alloy electrode

1 Introduction Many transition metal alloys with binary and ternary compositions have been studied as hydrogen evolution reaction electrodes in water electrolysis[1- 6]. The activity of such metal alloys for the hydrogen evolution reaction depends on at l…     

PRODUCTION OF THE PLATINUM ELECTRODE OF TANTALUM CLAD SILVER

This paper summarizes the production of the platinum electrode of tantalum clad silver. Ta(Ag). It clarifies the determination of the design parameters for the composite electrode, the technological process, the tensile test of the composite Ta(Ag) wire, the spotwelding of the electrode seal. the examination for leakage of the electrode. the prcess for winding the platinum foil and spotwelding, and the process parameter for obtaining high-quality electrodes during the production of 1,000 and more electrodes. The electrode produced satisfied the needs of the engineering design. It was demonstrated that the electrode had a long life-span and property stability, and fulfilled the norms for saving electricity and increasing production.     

PREPARATION AND ANALYSIS OF Ni-P-Zn ELECTROLESS DEPOSITION FROM ALKALT BATH

Electroless Ni-P-Zn alloys deposited from alkali bath were investigated in this paper. The deposition bath contained nickel sulfate, zinc chloride and hypophosphate. The process parameters, such as temperature, pH and zinc salt concentration were presented and discussed.The microstructure of the coatings was studied by XRD and SEM. The cathode glowing discharge characters of Ni-P-Zn depositions were studied with luminous Neon lamps. Electrodes deposited by electroless Ni-P alloys were apt to sputter during luminous working hours. Electroless Ni-P-Zn depositions improved the discharge characters of the electrodes.With the concentration of zinc in the deposition rising to 4wt%, electrode sputter was largely restrained. The thickness of the deposition also influenced the discharge characters of the electrode. To avoid electrode sputter, the concentration of zinc has to rise with the thickness of the depositions.     

Effect of process parameters on the efficiency of dye sensitized solar cells

The impact of process parameters on the efficiency of dye-sensitized solar cell (DSSC) was studied in order to improve its performance. TiO₂ working electrodes were prepared on FTO glass for various TiO₂ mixing time. Also these electrodes were sintered at four different temperatures (400, 450, 500, and 550°C) for one hour in ambient atmosphere. Platinum-sputtered counter electrodes were prepared at different light transmittance (70, 50, 30, and 0%). Microstructural charecterization of these electrodes were studied by X-ray diffraction method (XRD) and Scanning electron microscope (SEM). I–V characteristics of DSSCs made up of different working and counter electrodes were studied using solar simulator. Maximum efficiency (open circuit voltage (V_oc)∼0.68 V and short-circuit current density (J_sc) ∼ 12.3 mA/cm²) was observed for DSSC consisting of TiO₂ working electrode (12h mixing time, 500°C sintering temperature) and 0% transmittance Pt counter electrode. These results indicate that enhancement possibility of overall performance in DSSC was obtained by controlling process parameters, especially TiO₂ mixing time, sintering temperature and counter electrode transmittance.