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.

Effects of Yttrium on Lithium-aluminium Electrode

The effects of yttrium on the behavior of the lithium-aluminium alloy were studied by cyclic voltammetryand potential step. The electrochemical properties of lithium-aluminium anode were improved by adding yttri-um element into aluminium before lithium was deposited. Some parameters for preparing lithium-aluminiumelectrodes were also given.

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.

Electrocatalytic behaviour of Ni and NiCu alloy modified glassy carbon electrode in electro-oxidation of contraflam

The electrocatalytic oxidation of contraflam was investigated in alkaline solution on nickel and nickel–copper alloy modified glassy carbon electrodes(GC/Ni and GC/NiCu). We prepared these electrodes by galvanostatic deposition and the surface morphologies and compositions of electrodes were determined by energy-dispersive X-ray(EDX) and scanning electron microscopy(SEM). Cyclic voltammetry and chronoamperometric methods were employed to characterize the oxidation process and its kinetics. Voltammetric studies exhibit one pair of well-defined redox peaks, which is ascribed to the redox process of the nickel and followed by the greatly enhanced current response of the anodic peak in the presence of contraflam and a decrease in the corresponding cathodic current peak. This indicates that the immobilized redox mediator on the electrode surface was oxidized contraflam via an electrocatalytic mechanism. The catalytic currents increased linearly with the concentration of contraflam in the range of 0.25– 1.5 mmol/L. The anodic peak currents were linearly proportional to the square root of scan rate. This behaviour is the characteristic of a diffusion-controlled process. The determination of contraflam in capsules is applied satisfactorily by modified electrode.

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.

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.

电沉积铅合金在硫酸中循环伏安行为的研究

采用循环伏安法研究了铜上电沉积铅锡合金和铸造的铅合金在硫酸中的电化学行为,并且在多次循环后,比较两种电极的循环伏安曲线及表面形貌.结果表明:在硫酸电解液中,铜上电沉积铅锡合金电极表面发生的主要电化学反应,与铸造铅电极表面发生的主要的电化学反应基本相同,多次循环后电沉积铅锡合金电极具有更加均匀的表面形貌和组织结构.

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。

添加Co_3O_4的AB_5型贮氢合金的电化学性能

用恒流充放电、循环伏安、线性极化及交流阻抗等方法,研究了Co3O4对AB5型贮氢合金电极电化学性能的影响。掺杂电极更容易活化,在电压1.15 V处出现二次放电平台,与空白电极相比,添加5%与10%Co3O4电极的0.2C最大放电比容量分别提高21.2 mAh/g和36.0 mAh/g;掺杂电极的循环稳定性较好,添加5%与10%Co3O4电极第100次循环的容量保持率分别为95.73%和97.37%。电化学性能提高是因为部分Co3O4在碱性电解液中发生Co-Co(OH)2可逆氧化还原。Co3O4提高了电极表面的催化活性,降低了电荷转移电阻;适量添加Co3O4,有利于提高合金电极的大电流放电能力。

Electrochemical performance of a nickel-rich LiNi0.6Co0.2Mn0.2O2 cathode material for lithium-ion batteries under different cut-off voltages

A spherical-like Ni0.6Co0.2Mn0.2(OH)2precursor was tuned homogeneously to synthesize LiNi0.6Co0.2Mn0.2O2as a cathode material for lithium-ion batteries. The effects of calcination temperature on the crystal structure, morphology, and the electrochemical performance of the as-prepared LiNi0.6Co0.2Mn0.2O2were investigated in detail. The as-prepared material was characterized by X-ray diffraction, scanning electron microscopy, laser particle size analysis, charge–discharge tests, and cyclic voltammetry measurements. The results show that the spherical-like LiNi0.6Co0.2Mn0.2O2material obtained by calcination at 900°C displayed the most significant layered structure among samples calcined at various temperatures, with a particle size of approximately 10 μm. It delivered an initial discharge capacity of 189.2 mAh•g−1at 0.2C with a capacity retention of 94.0% after 100 cycles between 2.7 and 4.3 V. The as-prepared cathode material also exhibited good rate performance, with a discharge capacity of 119.6 mAh•g−1at 5C. Furthermore, within the cut-off voltage ranges from 2.7 to 4.3, 4.4, and 4.5 V, the initial discharge capacities of the calcined samples were 170.7, 180.9, and 192.8 mAh•g−1, respectively, at a rate of 1C. The corresponding retentions were 86.8%, 80.3%, and 74.4% after 200 cycles, respectively. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

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。

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。

贮氢合金电极的循环伏安和交流阻抗研究

贮氢合金电极的表面处理是改善其电化学性能的有效方法。通过MH电极的循环伏安和电化学阻抗谱研究了碱性溶液中MH电极表面还原处理对其电化学性能的影响。结果表明MH电极表面还原处理后 ,提高了电极的充电效率 ,改善了电极表面的电化学反应活性。通过对MH电极电化学阻抗谱的分析 ,发现这种处理明显降低了电极表面的电化学反应阻抗。

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。

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 .

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。

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.