Electrochemical Oxidation of Chlorimuron-ethyl on Ti/SnO2-Sb2O5/PbO2 Anode for Waste Water Treatment

<正>The electrochemical oxidation of chlorimuron-ethyl on Ti/SnO_2-Sb_2O_5/PbO_2 electrode was studied by cyclic voltammetry. The electrochemical behaviour of the electrode in a sodium sulfate solution and in the mixture solution of sodium sulfate and chlorimuron-ethyl was studied.The experimental results of cyclic voltammetry show that the acidic medium was suitable for the efficient electrochemical oxidation of chlorimuron-ethyl.Some electro-generated reagent was formed in the electrolysis process and chlorimuron-ethyl could be oxidized by the electro-generated reagent.A Ti/SnO_2-Sb_2O_5/PbO_2 electrode was used as the anode and the electrolysis experiment was carried out under the optimized conditions.The electrolysis process was monitored by UV-Vis spectrometry and high performance liquid chromatography(HPLC),and the chemical oxygen demand(COD) was determined by the potassium dichromate method.The mechanism of chlorimuron-ethyl to be oxided was studied primarily by the cyclic voltammetry and UV-Vis spectrometry.The results of electrolysis experiment demonstrate the possibility of the electrode to be used as an anode for the electrochemical treatment of chlorimuron-ethyl contained in waste water.     

Electrochemical characteristics of poly(ophenylendiamine) film electrodes in phosphatic solution

The electrochemical characteristics of poly(o-phenylendiamine) (POPD) film modified electrodes have been investigated using different electrochemical techniques.The main interest is focused on the effect of potential and film thickness on the electrode process.Good agreement has been found for the apparent diffusion coefficient estimated by chronocoulometry and impedance spec-troscopy.The charge transfer process within POPD films is diffusion processes at negative and positive overpotentials and electron hopping mechanism at formal potential.The POPD film conductivity of the oxidized state is better than that of the reduced state.For all electrode processes,the H+ may penetrate the film/electrolyte interface and take part in charge transfer or protonation-deprotonation of phenazine rings.     

A highly efficient electrochemical route for the conversion of aldehydes to nitriles

Using NH4 I as the supporting electrolyte as well as the precursor of an I2 promoter and nitrogen source, a highly efficient electrochemical route was developed to convert aldehydes to nitriles with excellent yields under mild reaction conditions. This electrochemical process could effectively avoid the direct use of NH3 gas, molecular iodine, and oxidants.     

Polymer engineering for electrodes of aqueous zinc ion batteries

With the increasing demand for scalable and cost-effective electrochemical energy storage, aqueous zinc ion batteries(AZIBs) have a broad application prospect as an inexpensive, efficient, and naturally secure energy storage device. However, the limitations suffered by AZIBs, including volume expansion and active materials dissolution of the cathode, electrochemical corrosion, irreversible side reactions, zinc dendrites of the anode, have seriously decelerated the civilianization process of AZIB...     

Characterization and Electrochemical Performance of ZnO Modified LiFePO4/C Cathode Materials for Lithium-ion Batteries

To improve the electrical conductivity of LiFePO4 cathode materials, the ZnO modified LiFePO4/C cathode materials are synthesized by a two-step process including solid state synthesis method and precipitation method. The structures and compositions of ZnO modified LiFePO4/C cathode materials are characterized and analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive spectroscopy, which indicates that the existence of ZnOhas little or no effect on the crystal structure, particles size and morphology of LiFePO4. The electrochemical performances are also characterized and analyzed with charge-discharge test, cyclic voltammetry and electrochemical impedance spectroscopy. The results show that the existence of ZnO improves the specific capability and lithium ion diffusion rate of LiFePO4 cathode materials and reduces the charge transfer resistance of cell, and the one with 3 wt% ZnO exhibits the best electrochemical performance.     

Universal Electrochemical／Chemical Simulator Based on an Exponentially Expanding Grid Network Approach

A universal simulator capable of simulating virtually any user-defined electrochemical/chemical problems in one-dimensional diffusion geometry was developed based on an exponentially expanding grid modification of the existing network approach. Some generalized reaction-diffusion governing equations of an arbitrary electrochemical/chemical process were derived, and program controlled automatic generation of the corresponding PSPICE netlist file was realized. On the basis of the above techniques, a universal simulator package was realized, which is capable of dealing with arbitrarily complex electrochemical/chemical problems with one-dimensional diffusion geometry such as planar diffusion, spherical diffusion, cylindrical diffusion and rotational disk diffusion-convection processes. The building of such a simulator is easy and thus it would be very convenient to have it updated for simulations of newly raised electrochemical problems.     

ELECTROCHEMICAL AND SPECTROELECTROCHEMICAL CHARACTERIZATION OF p-TRICYANOETHENYL-N,N-DIMETHYL ANILINE

The redox behaviours of a donor-acceptor model compound. p-tricyano-ethenyl-N, N-dimethyl aniline was investigated by electrochemical and spectroelectrochemical methods. The results indicate that charge transfer between the donor(amino) and the acceptor(cyanoethenyl) groups takes place in the process of oxidation of this compound.     

Synthesis and characterization of novel redox-active percec-type dendrons

Three novel redox-active percec-type dendrons were synthesized by mucleophilic substitution reaction of 11-bromoundecyl ferrocene and substituted benzoate.All the resultant ferrocenyl-modified dendrons were confirmed through FT-IR,NMR,and elemental analysis,etc.Furthermore,the thermal properties and electrochemical behavior of these dendrons were monitored with thermogravimetry analysis(TG),differential scanning calorimetry(DSC),polarized optical microscope(POM),and cyclic voltammetry(CV). Abound phase behavior and reversible electrochemical redox reaction process in the DMF solution of these dendrons was observed.     

Electrochemical Reduction of Nitrobenzene in Ionic Liquid BMImAc

Ionic liquid,1-butyl-3-methylimidazolium acetate（BMImAc）,was used in the electrochemical reduction of nitrobenzene.The electro-reduction of nitrobenzene on platinum electrode was studied by cyclic voltammetry（CV）,in situ Fourier transform infrared（FTIR） spectroscopy and constant-potential electrolysis.The experimental results show that electrochemical reduction process of nitrobenzene was controlled by diffusion,the main reduction product was azobenzen at-1.45 V,and the influences of scan rate and temperature on the electrochemical behaviors were obviously.A reduction mechanism of nitrobenzene in an ionic liquid was a probable ‘nitrobenzene→nitrosobenzene→azobenzene→aniline＇ main reductive reaction route.     

Core-shell structured SnSe@C microrod for Na-ion battery anode

The Sn Se nanoparticles encapsulated in the carbon nanofibers(Sn Se@C)with microrod morphology and core-shell structure are prepared by electrospinning and annealing process,and investigated as anode materials for sodium ion batteries.Benefiting from this unique structure,the Sn Se@C can deliver a reversible capacity of 283.8 m Ah g^-1 after 500 cycles at a high current density of 1.0 A g^-1.The sodium ion storage mechanisms of Sn Se are further characterized by ex-situ X-ray diffraction,high-resolution transmission electron microscope and selected area electron diffraction measurements.Besides,the excellent electrochemical performance of the electrodes is investigated by pseudocapacitance and in situ electrochemical impedance spectroscopy measurements.This work may provide a new avenue for synthesis of metal selenides with core-shell structure and a good idea for studying the kinetics process.     

单体动态电化学

由于个体的差异性和异质性作用,整体平均测量掩盖了个体的本征性质和电化学性能之间的关联.单体碰撞电化学作为一种强大而方便的电化学方法,已被用于研究超微电极上自由扩散的单个个体随机碰撞过程中的电化学行为.然而,个体的动态行为与其电化学反应过程息息相关.因此,对于单体动态电化学行为的研究可实时获取单体在电极界面上的动态电化学...     

Layer-by-layer assembly of silicotungstate multilayer films modified on glassy carbon electrode and their electrochemical behaviors

A new electrode was modified by multilayer films composed of heteropolyanion (SiW12) and cationic polymer poly(diallyldimethylammonium chloride) through electrochemical growth. The modified electrode electrochemical behavior, the effect of solution pH and electrocatalytic response to the reduction of BrO3- and NO2- have been investigated. The result shows that the electrochemical process of multilayer films modified electrode including SiW12 is a reversible process by electrochemical step. One-electron process has no proton participation in the first step, and one-electron process is accompanied by one proton participation in the second step and two-electron process is accompanied by two protons participation in the third step. The films grow uniformly, and the peak currents increase with increasing layer numbers. The peak currents increase with scan rate, and the reduced potentials of multilayer films shift negatively with increasing pH. The electrochemical mechanism of multilayer films was suggested.     

Ti/SnO2-Sb2O5/PbO2阳极电化学氧化降解咪草烟及其过程监测

电催化高级氧化技术是最近发展起来的新型高级氧化技术之一,具有处理效率高、操作简便、与环境兼容等优点。因此,电化学水处理工艺在无机废水和高浓度、难降解有机废水处理中得到了越来越广泛的应用[1,2]。钛基二氧化铅(Ti/PbO2)是一种新型的不溶性金属氧化物阳极材料,在水溶液     

Evidence for the occurrence of electrochemical reactions and their interaction with chemical reactions during the corrosion of pure Fe with solid NaCl deposit in water vapor at 600 °C

The results of this work prove that electrochemical reactions are involved in the whole corrosion process of pure Fe with a solid NaCl deposit in water vapor at 600 °C. The interaction of chemical and electrochemical reactions accelerates the corrosion rate of pure Fe significantly. The electrochemical reaction is coupled with a preceding chemical reaction process (ce), in which Fe first reacts chemically with NaCl and water vapor to generate HCl_(g). And then, the electrochemical reaction proceeds via a one-electron electrochemical reduction to form H₂.     

Three-phase electrochemistry for green ethylene production

The electrochemical conversion of greenhouse gases (mainly CO₂ and CH₄) into ethylene has attracted worldwide attention. Compared with thermal cracking and dehydrogenation ethylene production processes, electrochemical ethylene production is an energy-saving and environmentally friendly process with high atom and energy economies. Great efforts have been made in enhancing the performance of electrochemical CO_x reduction and alkane dehydrogenation reactions in recent years. The complicated interactions between gas reactants, electrolytes, and catalysts force the three-phase interface mass transfer process an important issue in determining the electrochemical activity and product selectivity. Herein, we summarize the recent progresses on electrochemical ethylene production. Special attention has been paid to the principles for the design of gas–liquid–solid and gas–solid–solid three-phase interfaces and their influence on the electrochemical CO_x reduction and alkane dehydrogenation reactions. The comprehensive understanding of those different ethylene production reactions together from the perspective of the three-phase interface-related mass transfer process would provide new insights into the design of advanced electrochemical cells for green ethylene production.     

电化学技术在选磷回水利用中的应用

研究表明,浮选磷矿的废水经电化学处理后可循环利用．通过改进的方法测定废水中悬浮颗粒的ζ电位和废水的透光率,可确立电化学处理的适宜参数．     

靛蓝胭脂红波薄层光谱电化学研究(I)

采用SnO_2石英玻璃组装的光透薄层电解池, 结合紫外可见光谱现场监测技术, 研究了靛蓝胭脂红水溶液的电化学还原与氧化过程. 测定了不同pH下的式电极电位(E~0)和电子转移数(n). 实验结果表明, 靛蓝胭脂红在SnO_2电极上的还原为准可逆的两电子转移过程, 而它的氧化则为不可逆电极过程. 由电解现场检测的光谱, 初步探讨了电解还原与氧化的反应机理。     

A novel efficient numerical method to simulate electrochemical process for a lithium ion battery

The simulation plays an important role in understanding of electrochemical behavior and internal process of lithium ion batteries. The existing finite difference method (FDM) to conduct the simulation of electrochemical process is time-consuming and computationally expensive. In this paper, a novel numerical method is proposed to accelerate the solution of the electrochemical model for a lithium ion battery. It is implemented in three steps. In the first step, physical analogy of electrochemical process to an electric circuit is used to solve charge conservation equations. In the second and third step, control volume method is used to solve species conservation equations. The simulation results show that the proposed method is much faster than the FDM by 2.2 times while maintain high accuracy which is verified by simulation and experimental data as well.     

维生素K3电化学反应机理的红外光谱电化学研究

用循环信安法及现场红外光谱电化学法研究了维生素Ｋ３在铂电极上,弱碱性水溶液介质中的电化学反应机理。循环伏安法实验结果显示ＶＫ３的电反应为两步电子准可逆电极过程,现场光谱电化学实验结果则从基团特征吸收频率的变化表明了ＶＫ３的电化学还原和氧化经历了从萘醌到萘酚的互变过程。据此进一步证实了ＶＫ３由萘醌到酚的电化学反应机理。     

席夫碱自组装单分子膜的电化学行为

利用自组装技术将席夫碱硫醇衍生物在金表面形成自组装单分子膜,并初步研究了此自组装单分子膜的电化学行为,发现该席夫碱分子在0.1 mol•L－1的KCl溶液中具有电化学不可逆氧化还原行为，且随着自组装时间的增加表观电极反应速率常数值显著减小,最后减小为0,并对此进行了解释.