Electrode Process of Y^(3+) Ion on Copper Electrode and Surface Alloying

The reduction of yttrium ion on copper electrode in NaCl-KCl-YCl3 molten salts has been investigated.The results indicate that several humps for formation of intermetallic compounds occur before metallic yttrium is produced. The formation of intermetallic compounds is controlled by diffusion of yttrium into copper electrode. The application of theoretical results to diffusion of yttrium atoms into copper substrate is discussed also.

Electrode Process of Y（Ⅲ）on Nickel Electrode and Surface Metallizing

In this study, the electrochemical reduction of Y(Ⅲ)on nickel electrode has been investigated. The resultsshow that there are several plateaus for formation of intermetallic compounds preceding reduction peak ofyttrium. A linear relationship between the current and t￣(-1/2) has been obtained, showing that Cottrell's law isobeyed.

Electrochemical study of different membrane materials for the fabrication of stable,reproducible and reusable reference electrode

Fabrication of stable,reproducible and reusable reference electrodes for low energy and high-temperature steam splitting is of great interest for hydrogen fuel production without anthropogenic carbon dioxide(CO2)emission.This study has been conducted for the detection of suitable material for the fabrication of novel reference electrode.In the present scenario,this research is designed to fabricate a novel nickel reference electrode by using operating conditions of eutectic molten hydroxide(NaOH-KOH,49-51 mol%)at temperature 300℃in an ion-conducting membrane of alumina and mullite tube.Afterwards,the designed nickel reference electrode has been examined for its reusability and stability by using electrochemical technique and cyclic voltammetry.Five scans of cyclic voltammetry are performed for both membrane fabricated reference electrode.A slight positive shift in oxidation peaks is observed for mullite membrane electrode(64 mV from scan 1 to 5).The stability measurements are noted by changing the scan rate between 50 and 150 mV s−1.Furthermore,the results show that the Ni/Ni(OH)2 reference electrode covered with a mullite membrane is stable and reusable at 300℃temperature without any deterioration.The stability and reusability of prepared nickel reference electrode covered by mullite tube in the eutectic molten hydroxide were up to 9 days to carry out an electrochemical investigation,while for alumina tube reference electrode the stability and reliability were up to 3 days.The internal electrolytic material and ionic conductance can play an important role for future studies with this reference electrode along with optimisation of temperature and scan rate parameters.

循环伏安法原理的分析与讨论

循环伏安(CV)法是重要的电化学研究方法之一。然而大学仪器分析课程中只对其测量原理作了简单陈述,而未对测试过程中发生的电极反应作深入介绍,使学生无法深刻理解CV曲线的含义。本文从电极反应过程入手,讨论了电极/界面处电活性物质浓度随电势变化的规律,以及浓度和扫描速度等对CV曲线的影响。最后,剖析了蕴含在CV中的哲学原理。本讨论可为教学提供一定的参考。

舒乐安定在铂离子注入修饰电极上的电化学行为及其应用

舒乐安定在0.1 mol/L NH3-NH4Cl缓冲溶液(pH 9.40)中,用线性扫描伏安法,在Pt/GC离子注入修饰电极上,形成一良好的线性扫描伏安还原峰,峰电位Ep=-0.70V(vs.SCE)。其峰电流与舒乐安定浓度在3.0×10-9-1×107和1×10-7-1.5×10-6mol/L范围内呈线性关系,相关系数均为0.9999,检出限为3.0×10-9mol/L。并用于片剂的测定,回收率在96.5％～98.5％之间,结果是可靠的。用循环伏安法研究了体系的性质。实验表明,电极过程为不可逆吸附。用AES、XPS和SEM等表面分析方法证明,Pt离子确实注入到玻碳基体电极表面,Pt以原子态存在,催化了舒乐安定的还原。

络合吸附催化循环叠式方波伏安法

对受前行化学反应控制的络合吸附催化体系循环叠式方波伏安法进行了理论推导和实验验证，讨论了电流的特性。结果表明，对于络合吸附催化体系的测定，循环叠式方波伏安法的灵敏度比现行方波伏安法高约２５倍。

钇离子在铜电极上的电极过程及表面合金化

钇离子在铜电极上的电极过程及表面合金化周春根，段淑贞（北京科技大学理化系，北京１０００８３）通过熔盐电化学表面合金化方法获得的镀层非常均匀、无裂纹，具有很强的抗腐蚀性能，其原因是获得的合金镀层系由一种金属原子向另一种基体金属表面扩散的结果￣［１，２］...

络合吸附催化不可逆循环叠式方波伏安法

研究了络合吸附催化不可逆体系受前行化学反应控制（Ｋ １）和不受前行化学反应控制（Ｋ １）两种情况下的循环叠式方波伏安法的电流理论，并进行了实验验证，讨论了电流特性，获得区分Ｋ １和Ｋ １的判据。对于上述体系的测定，循环叠式方波伏安法的灵敏度比普通差式采样方波伏安法高一个数量级以上。

铈对锂在铝电极上电极过程的影响

利用循环伏安法和计时电流法研究了铈在铝电极上的电极过程和铈对锂在铝电极上电极过程的影响。铈不仅改善了锂铝合金的电化学性能，而且改进了铝基体材料的物理性能。为制备锂铝合金阳极提供了依据。

硫化亚铁阴极的电极过程机理

应用循环伏安法研究了硫化亚铁阴极的电极过程机理 ,电极反应过程伴随着难溶硫化亚铁的形成与溶解 ,该电极过程受欧姆电阻控制 .根据循环伏安曲线峰电流和峰电位与扫描速度平方根成线性关系 ,提出了电极过程的欧姆电阻控制模型 ,导出峰电位和峰电流与扫描速度之间的关系式 ,理论分析与实验结果一致 .

Electrochemical behavior of Li incorporation in Al in LiTFSI/KTf molten salt electrolyte

The electrochemical behavior of lithium incorporated in aluminum electrode in LiTFSI/KTf （lithium bis （trifluoromethylsulfonyl） amide/CF3SO3K） molten salt electrolyte was studied by a variety of electrochemical techniques including cyclic voltammetry, chronopotentiometry and chronoamperometry. The reduction reaction is found involving a nucleation process on the aluminum electrode. The results of chronopotentiometry indicate that the process of lithium incorporation in aluminum is smooth and uniform. The galvanostatic cycle experiments show that the coulombic efficiency is very low in the first cycle, which is mainly due to the ＂retention capacity＂ of Li-Al alloys. This characteristic is testified by the results of XRD and SEM. The results of chronoamperometry indicate that the incorporation of lithium into aluminum for the formation of a-phase Li-Al alloy is limited by its diffusion rate, with a measured diffusion coefficient of 1.8× 10^-10 cm2/s.

抗坏血酸在多壁碳纳米管修饰电极上电极过程的研究

运用循环伏安(CV)法、计时电量法和稳态极化曲线法研究了抗坏血酸(AA)在多壁碳纳米管修饰玻碳电极(MWCNT/GCE)上的电化学行为.实验表明:AA在MWCNT/GCE上的电极过程为扩散控制的不可逆过程,其极限扩散电流id为1.500×10-5A,扩散系数D0为1·634×10-5cm2/s,标准电极电势时的电极反应速率常数ks为1·694×10-3?/s.

含铝络合离子在铜电极上的电沉积

采用循环伏安法研究了含铝络合离子在铜电极上的电沉积,以探明含铝络合离子在铜电极上的电极过程及表面合金化.循环伏安结果表明,含铝络合离子在铜电极上还原时,铝络合离子首先被还原为金属铝,接着生成的金属铝与铜基体形成铜铝合金.电沉积实验后采用扫描电子显微镜、能谱仪和X射线物相分析仪对样品进行形貌表征及成分分析,扫描电镜及样品侧面线扫描照片结果表明,含铝络合离子在铜电极上析出时与铜基体形成合金,具有明显的过渡层.X射线物相分析结果表明合金为AlCu和Al2Cu,这与铝在铜电极上的循环伏安曲线相吻合,即生成两种新的产物铜铝合金.

Mn^(3+)/Mn^(2+)氧化还原体系的旋转圆盘电极法性能

The electrochemical behaviors of Mn 3+ /Mn 2+ redox couple used as the cathodic electroactive material in a new electrochemical storing energy system (redox flow cell) were studied by means of RDE techniques on platinum electrode.The experiment results showed that kinetics of electrode process was controlled by mass transported on the static Pteledtrode;and on RDE electron transfer and/or mass transport could become the rate controlling step of the electrode process depending on the magnitude of the overpotential and the rotating speed of RDE.

Ln^(3+)在LnF_3-LiCl-KCl熔盐体系中的电化学行为

钍的分离和再利用是熔盐堆钍铀燃料循环的重要组成部分,钍与裂变产物特别是化学性质相似的镧系元素的分离是熔盐堆氟盐燃料处理的关键之一。利用循环伏安法和方波伏安法研究了773 K下多种镧系元素氟化物(w=3%)在LnF_3-LiCl-KCl熔盐中的电化学行为。研究结果表明:Ce^(3+)和Gd^(3+)在惰性电极上均一步还原为金属,Nd^(3+)则是通过两步反应还原为金属,而Sm^(3+)和Eu^(3+)只能还原为低价态的Sm^(2+)和Eu^(2+);Th和Ln在惰性金属阴极上的析出电位差ΔE均大于0.19 V,在LiCl-KCl熔盐体系中实现Th与Ln的电化学分离在理论上是可行的;与纯氯盐体系相比,少量F-的引入不会改变Ln^(3+)在惰性电极上的电极反应过程,F-的存在使得Ln^(3+)在LiCl-KCl熔盐中的活度降低,从而导致扩散系数减小。此研究结果为了解Th4+)和Ln^(3+)在含F-氯盐体系中的电化学行为和建立可行的分离方法提供了基础实验依据。

萘乙酸电化学降解机理研究

用三电极体系循环伏安法研究了萘乙酸溶液体系的电化学行为,对萘乙酸的电极还原-氧化过程及其可逆性、控制因素进行了探索性研究;研究了温度、扫描速率、通氮除氧、硫酸钠、扫描次数等因素对萘乙酸溶液电极过程的影响.该研究结果为环境中萘乙酸电化学处理工艺的选择提供了参考依据.

基于Origin软件的循环伏安实验数据处理

以涂层电极氧化物的研究为例,具体介绍了基于Origin 8.5软件对循环伏安实验测得的实验数据进行处理和分析的方法。通过将扫描速率与电流密度和伏安电荷相关联,获得涂层电极表面电催化活性、表面粗糙度、内外活性表面积等重要实验结果,为本科毕业生关于电极材料、超大电容器等相关项目研究进行数据处理和分析时提供借鉴和参考。

苄基紫精在金、铂电极上的伏安特性

用循环伏安法研究了磷酸盐缓冲溶液（ｐＨ６．８）中苄基紫精（ＢＶ２＋）在金、铂电极上的伏安特性．考察了电位扫描下限（ＥＬ）、扫描速度（ｖ）、ＢＶ２＋浓度等因素对ＢＶ２＋电极过程的影响．在－０．４～０．９Ｖ（ｖｓ．ＳＣＥ）电位区，ＢＶ２＋的还原表现为两个阴极峰．当ＥＬ正于第二个还原峰电位时表现为可逆的ＢＶ（２＋／＋）氧化还原过程．当ＥＬ负于时，生成完全还原产物一中性紫精ＢＶ°，其氧化过程强烈依赖于ｖ和紫精浓度．在低浓度下，当高扫描速度时可观察到ＢＶ的可逆氧化；在高浓度下，即使扫描速度很高仍表现为不可逆的氧化过程．伏安特性中的异常现象用电荷转移络合物的形成予以解释．

法拉第吸脱附偶联过程循环伏安行为的有限元分析

法拉第吸脱附偶联过程的电化学行为较为复杂,难以定量获得其表界面反应动力学信息.本文通过COMSOL有限元软件对法拉第吸脱附偶联过程的循环伏安行为进行数值分析,研究了反应物或产物不同吸附条件下的循环伏安行为.结果表明:当反应物或产物弱吸附时,可通过阴、阳极峰电流之差实现饱和吸附量的定量表征.随着吸附平衡常数的增大,反应由弱吸附向强吸附过渡,峰电流由扩散峰与吸脱附峰相互重叠过渡到相互分离的吸脱附"前波"或"后波"特征.该吸脱附特征峰的形状和位置与电势依赖的吸附平衡常数有关.吸附平衡常数及其电势依赖程度越大,吸脱附峰偏离扩散峰越远,吸脱附峰越尖锐.该模型为法拉第吸脱附偶联过程的循环伏安研究提供了一种定量研究方法,能够帮助研究者从复杂的吸脱附伏安行为中定量获得饱和吸附量和吸附平衡常数等信息,并对涉及吸脱附的电催化研究具有一定指导意义.

Effect of Cerium on Lithium-Aluminium Anode

The electrode kinetics of cerium on aluminium electrode and its effects on the behavior of the lithium-aluminium anode were studied by using cyclic voltammetry and chronoamperometry. The electrochemical properties and physical behavior of lithium-aluminium anode were improved by adding cerium into aluminium before lithium was deposited. Some parameters for preparing lithium-aluminium electrodes were also given.