Chemistry Commons^™

Electrochemical Separation Of Curium And Americium, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

The objectives of this project are to use electrochemical techniques to develop a thermodynamic understanding of actinide and lanthanide species in RTIL solution, and to use this data to effectively separate species with very similar chemical properties. In consultation with a national laboratory collaborator, electrochemical methods and materials will be evaluated and used to exploit the thermodynamic differences between similar chemical species, enhancing the ability to selectively target and sequester individual species from mixtures. This project is in its third year and has successfully completed phases 1 and 2. Phase 3 has been partially completed. The tasks have been expanded …

F-Element Electrochemistry In Room Temperature Ionic Liquids, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

This proposal focuses on f-element electrochemistry in room temperature ionic liquids (RTILs). The ultimate goal is to fully characterize the oxidation/reduction of elements in RTILs to establish the baseline thermodynamic and kinetic data for these systems. The data will be used to critically evaluate the ability to use electrochemical methods for controlled, potential mediated, separation off-elements by electroplating on electrodes surfaces. Factors that will influence the ability to measure the redox processes in f-elements in RTIL solutions and electroplating on electrode surfaces include the structure, solubility, and stability of the target species in these solutions. These factors will be addressed …

Preparation And Electrochemical Characterization Of Anatase Tio2 Nanotubes, Bin Cao, Jin-Wei Xu, Ling-Hong Ding, Wei-Feng Zhang

Journal of Electrochemistry

Titanium oxide nanotubes were prepared by hydrothermal treatment of anatase-type TiO₂ powders and NaOH solution in an autoclave.Transmission Electron Microscopy and X-ray Diffraction showed that the product is anatase-type TiO₂ nanotubes.The constant charge-discharge current and cyclic voltammetry exhibited the TiO₂ nanotubes have a large initial lithium insertion capacity of 260 mA·h/g and good reversibility.This study indicates that TiO₂ nanotubes might be a good negative electrode materical for second lithium battery in the future.

Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

Nano materials and nano technology receive great attention all over the world.While electrochemistry has already achieved a great application in industry and it has proved that electrochemistry will play an important role in the field,such as energy source,new materials,life sciences,information sciences,environment and nano sciences.In this paper,the recent developments of electrochemical techniques for the preparing nano materials,application of nano materials in the areas of electrodeposition,batteries,electrocatalysis,sensors are introduced in brief.

The Electrochemical Separation Of Curium And Americium: Quaterly Report January - March, 2006, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

This research report outlines the current status and progress associated with the electrochemical separation of Curium and Americium. For two and a half years, research has been actively performed on this project, and is currently on schedule for the proposed timelines.

Progress:

• The electrochemical characterization of Ce and Eu complexed with EDTA, NTA, and Citrate has been completed.

• Synthesis of the polymer substrate and the chelating ligand is underway. Approximately 50 grams of disulfide has been produced to produce the chelating thiol group required for the last set of studies.

• Gold substrates have been prepared to perform …

Effect Of Applied Potentials On The Formation Of Self-Assembled Monolayers Of Alkanethiol, Peng Diao, Xiao-Ning Wang, Qun-Chao Hou, Min Guo, Min Xiang, Qi Zhang

Journal of Electrochemistry

The self-assembled monolayers(SAMs)of n-dodecanethiol were prepared on gold substrates under electrochemical conditions using potential step technique.Electrochemical impedance spectroscopy was employed to characterize the SAMs prepared under different substrate potentials.It is found that the potential applied to gold substrate has great influence on the formation of SAMs.Within potential regime-0.8 V to 1.2 V,the increase of applied potential firstly leads to the formation of SAMs with higher packing density,better ordering and less defects.However,after reaching the maximum at 0.4 V,the packing density and the ordering of SAMs begin to deteriorate when the substrate potential is further increased.This work provides solid experimental basis for …

Electrochemical Reduction Behavior Of Benzaldehyde In The Ionic Liquids, Ning Zhao, Wen-Ju Dong, Qi-Zeng Shi

Journal of Electrochemistry

In this paper, the electrochemical reduction of benzaldehyde was investigated in C₄MIMBF₄, C₆MIMBF₄  and C₈MIMBF₄ ionic liquids by cyclic linear sweep voltammetry,cyclic square-wave voltammetry and chronocoulometry.Benzaldehyde exhibits two successive one-electron irreversible reduction(E_P1=-1.39 V, E_P2=1.69 V) with GC electrode in C₄MIMBF₄, the voltammetric data for benzaldehyde give diffusion coefficients of 1.5*10^-8cm²/s and 1.3*10⁸cm²/s. There is one current peak in C₆MIMBF₄  and C₈MIMBF₄ ionic liquids due to their stronger alkalinity …

Electrochemical Separation Of Curium And Americium, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

The objective of this project is to use electrochemical techniques to develop a thermodynamic understanding of actinide and lanthanide species in aqueous solution and use this data to effectively separate species with very similar chemical properties. In consultation with a national laboratory collaborators, electrochemical methods and materials will be evaluated and used to exploit the thermodynamic differences between similar chemical species enhancing the ability to selectively target and sequester individual species from mixtures. This project is in its third year and has successfully completed Phases 1 and 2.

The following were specific goals for this year:

• To develop a fundamental …

The Electrocatalystic Investigation Of 3,4-Dihydroxybenzoic Acid On The Modified Multiply Wall Carbon Nanotubes, Ming-Qi Li, Duo-Chang Cai, Xiao-Ying He

Journal of Electrochemistry

The electrochemical behavior of 3,4-Dihydroxybenzoic acid(DHBA) on modified multiply wall carbon nanotubes electrode was investigated by cyclic voltammetry(CV) and square wave voltammetry(SWV). Results show that in 0.1 mol/L HCl solutions the modified carbon nanotube electrode has an obvious electrocatalytic effect on the oxidation and deoxidization of DHBA. The oxidation current of DHBA is linear to it's concentration in the range of 4.0×10^-6～1.0×10^-4 mol/L and 2.0×10^-4～8.0×10^-4 1mol/L with correlation coefficient of 0.9995 and 0.9992. The detection limit is 1.0×10^-6 mol/L.

Electrochemical Properties Of Aloe Emodin In Aqueous And Nonaqueous Solvents, Li-Ying Huang, Zhong-Cheng Wang, Li-Min Lai, Xin-Hua Lin, Wei Chen

Journal of Electrochemistry

Electrochemical properties of Aloe emodin in aqueous and nonaqueous solvents of DMSO were studied by cyclic voltammetry and linear sweep voltammetry at a platinum electode. A pairs of currents on the voltammogram may be attributed to a quasi-reversible-one-electron transfer in HAc-NaAc and DMSO, the peak potential in DMSO was found to move more negatively compared with that in HAc-NaAc. A new method for Aloe emodin determination is described. The peak current is proportional to the concentration of Aloe emodin over the ranges of 1.0×10^-5~6.0×10^-4 mol/L. The electrochemical properties of Aloe emodin were related to solvents.

Electrochemical Remedy And Analysis For The Environment Based On The New Polymer-Dna Composite Material., Noor Feuza Hussain

Electronic Theses and Dissertations

In this work a new material, the conducting polymer-DNA composite, has been reported for the first time due to its promise in micro extraction, transfer, and release of cations under controlled potential conditions by using electrochemically assisted solid phase micro extraction (SPME). The Polypyrrole/DNA composite can be formed easily by oxidation of pyrrole monomers in the presence of chromosomal DNA by electropolymerization. Environmental significant pollutants such as Cd, Pb, Hg, Co, Zn, Cu, and Bi metal ions can be extracted from the aqueous solution and are able to be transferred to another medium defined as the release solution where the …

The Electrochemical Separation Of Curium And Americium: Quaterly Report April - June, 2005, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

This research report outlines the current status and progress associated with the electrochemical separation of Curium and Americium.

Results

• We have completed the electrochemical investigation in of the Ce³⁺/Ce⁴⁺ redox couple and have determined the optimum experimental conditions.

• Computer modeling of the cerium using the JChess speciation-modeling program has been completed for the Ce redox couple. Traditional complexing ligands such as EDTA, oxalate, NTA, phosphate, acetate, and sulfate have been purchased and will be used to initiate the complexation and electrochemical characterization.

• Electrochemical investigations have continued on the Eu²⁺/Eu³⁺ redox …

Studies On Polymer Light-Emitting Electrochemical Cells ——Introduction Of The Studies On The Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids (Ⅱ), Yong-Fang Li

Journal of Electrochemistry

Polymer light-emitting electrochemical cell (LEC) is composed of a conjugated polymer(CP)/polymer electrolyte blend film sandwiched between an ITO anode and an Al cathode. When a bias voltage greater than Eg/e (where Eg is the energy gap of the CP, e is the electron charge) is applied on the two electrodes, the CP in the polymer blend film at the anode side will be oxidized (to form a p-doped region), and that at the cathode side will be reduced (to form a n-doped region), then a p-i-n junction will be produced. Light-emission occurs in the intrinsic region between the p- and …

Application Of Carbon Paste Electrode On The Electrogenerative-Leaching Process Of Sulfide Minerals, Shao-Fen Wang, Zheng Fang, Yun-Yan Wang

Journal of Electrochemistry

The cyclic voltammetry curves of sulfide mineral electrodes or corresponding carbon paste electrodes in NaCl electrolytes have been obtained in this study. The experimental results indicate that acetylene black (revealed) the electro-catalytic propertyin the electrogenerative-leaching process of sulfide minerals. The output currentand potential of carbon paste electrodes were increased to some degrees while the activation energies were lower.

Electrochemical Separation Of Curium And Americium, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

The objective of this project is to use electrochemical techniques to develop a thermodynamic understanding of actinide and lanthanide species in aqueous solution and use this data to effectively separate species with very similar chemical properties. In consultation with our DOE collaborator, electrochemical methods and materials will be evaluated and used to exploit the thermodynamic differences between similar chemical species enhancing our ability to selectively target and sequester individual species from mixtures.

The following were specific goals for this year:

• To develop a fundamental understanding of the thermodynamic properties of actinide and lanthanide species such as Cm, Am, Ce, Nd, …

The Electrochemical Separation Of Curium And Americium: Quaterly Report August-December 2004, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

This research report outlines the current status and progress associated with the electrochemical separation of Curium and Americium. The following pages outline the progress on our project to date. We have been actively performing research on this project for three months and are currently on schedule in terms of the proposed timelines.

The initial focus of the project involved setting up the laboratories for the studies outlined in the grant proposal. The instrumentation needed included an electrochemical work station that will perform the bulk of the electrochemical studies. This instrument will complement the electrochemical instrumentation in Dr. Hatchett’s laboratory and …

Chemical Microetching Of Three-Dimensional Gear-Like Pattern On Nickel Surface, Zhu-Fang Liu, Li-Ming Jiang, Jing Tang, Li Zhang, Zhong-Qun Tian, Zhao-Wu Tian, Pin-Kuan Liu, Li-Ning Sun

Journal of Electrochemistry

The chemical micromachining on nickel surface with three-dimensional (3D) gear-like mold was realized by confined etchant layer technique (CELT). By using effective chemical etching and scavenging system (HNO₃ +NaOH) and optimizing experimental parameters, such as the etching time, etching current density, concentration of the etchant or and scavenger, we obtained the etched pattern, which is close to negative copy of the mold. The etched micro-pattern characterized by SEM and AFM, demonstrates that CELT can be applied to the 3-D microstructure replication on nickel surface.

Studies On The Electrochemical Behavior Of Copper Paratolysulfate And Its Complexes, Ji-Guo Song, Pei-Kang Shen

Journal of Electrochemistry

Copper (II) paratolysulfate has been synthesized and characterized by thermo-gravimetric (TG) measurements and differential scanning calorimetric (DSC) analysis. This salt can easily lose all crystal water and the dehydrated salt does not deliquesce in the air. It is found for the first time that the complex of Cu(p-OTs)₂/ethanolamine(1∶1) can catalyze the oxidation of 1,1′-bi-2-naphthol in DMSO and DMF, while the process is difficult to perform in H₂O and CH₃OH. The electrochemical behaviors of both Cu(p-OTs)₂ and its complexes with ethanolamine have been studied on platinum electrode in DMSO, DMF, CH₃OH and …

Synthesis Of (S)-3-Phenylpropane-2-Tert-Butoxycarbonylamino-1-Thiol And Its Electrochemical Behavior Self-Assembled On Gold, Ru Sun, Jian-Feng Ge, Mei Wang, Ren-Ao Gu

Journal of Electrochemistry

The synthesis of (S)-3-Phenylpropane-2-tert-butoxycarbonylamino-1-thiol(N-Boc-APT) from L-phenylalanine was reported. L-Phenylalanine was reduced to the corresponding amino alcohol, protection of the amino group using tert-butyl pyrocarbonate gave (S)-2-tert-butoxycarbonylamino-3-phenylpropane-1-ol, which was then O-mesylated and treated with potassium thioacetate in DMF to give 3-phenylpropane-2-tert- butoxycarbonylamino-1-etylmercapto. After the acetyl group was removed with ammonia in alcohol, the desired target molecular was obtained. The structure of intermediate and target molecular was conformed by IR and ¹HNMR. We made N-Boc-APT self-assemble-modificated gold electrode and investigated its electrochemical behavior. The CV results of methylene blue on nano-Au/N-Boc-APT SAM/Au electrode showed that nano-Au could speed this electron transfer …

Electrochemical Separation Of Curium And Americium, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

The objective of this project is to develop a method for the separation of Am from Cm based on electrochemical techniques. Electrochemical systems that allow the thermodynamics of actinide and lanthanide complexes to be systematically evaluated and tuned will be examined. The influence of complex formation on the ability to selectively isolate a given species electrochemically will be evaluated. Metal-ligand complex formation provides a useful derivation technique to increase solubility in solution environments that favor precipitation. In addition, the thermodynamic properties of a complex relative to the isolated species may be shifted to more suitably measurable electrochemical separation regimes. Electrochemical …

The Electrochemical Separation Of Curium And Americium: Quaterly Report January - March 2004, David W. Hatchett, Kenneth Czerwinski

Separations Campaign (TRP)

This research report outlines the current status and progress associated with the electrochemical separation of Curium and Americium.

Data collection and analysis of the Ce³⁺/Ce⁴⁺ redox couple in various supporting electrolytes has continued. All electrolyte systems were investigated at Pt, Au, and Glassy Carbon working electrodes. Analysis of these data was accomplished by performing appropriate background subtractions to reveal net peaks due to Ce redox behavior. Successful identification of the Ce redox couple was achieved with all electrolyte/electrode systems, although a decline in peak resolution was observed with increasing acid concentration. Optimal conditions in this experiment were …

The Activity Of Silicon Carbide Particles In Al-Based Metal Matrix Composites Revealed By Scanning Electrochemical Microscopy, David O. Wipf, L. Díaz-Ballote, L. Veleva, M. A. Pech-Canul, M. I. Pech-Canul

CAS Publications

Scanning electrochemical microscopy (SECM) is used to image variations in electrochemical activity over the surface of an aluminum-based metal matrix composite (MMC) in contact with buffered or unbuffered neutral solutions. The composite consists of an Al - 13.5% Si - 9% Mg alloy matrix and reinforcing silicon carbide particles (SiC_p). Feedback mode SECM imaging using ferrocenemethanol as a redox mediator in 0.1 M NaCl solution and in buffer solution (pH 6.8) revealed that the SiC particles are electrochemically active. The data suggest that the electronic conductivity at these sites is higher than that of the Al₂O …

Synthesis, Characterization And Physical Studies Of Ligand Bridged Bimetallic Aqua Ruthenium (Ii) Polypyridyl Complexes, Matthew Thomas Mongelli

Seton Hall University Dissertations and Theses (ETDs)

.

A Bilayer Self-Assembled Membrane Electrode For Fluorescence And Its Electrochemical Characterization, Xiang-Ying Sun, Bin Liu, Yun-Bao Jiang

Journal of Electrochemistry

The bilayer membrane was assemblied on Au electrode by the electrostatic interaction between the fluorescence regent 1-naphthylamine diacetate acid (NADA) and DL-Cysteine. The SAMs electrode NADA/Cys/Au can be used as fluorescence and electrochemical sensor for metal ions. This paper states the electrochemical characterization of NADA/Cys/Au and SAMs' application in continous determination for Cu²⁺ and Ni²⁺.

The Electrochemical Behaviors Of A Novel Ferrocene Alkylthiol Sams On Au Electrode, Xiao-Gang Zhang, Yan-Li Shi, Hu-Lin Li

Journal of Electrochemistry

A novel alkylthiol molecule containing ferrocene and pyridium moieties and its hydrogenated products were synthesized and subsequently assembled on Au electrode as SAMs. Cyclic voltammogram(CV) was used to investigate the structure-dependent electrochemical response of the SAMs in 0.1 mol/L HClO₄ aqueous solution.

Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin

Journal of Electrochemistry

Metallic nickel was electrochemically dissolved in absolute ethanol and acetylacetone mixed solutions and in the presence of Bu₄NBr (as an electron-conductive additive). The electrolyte solution containing the precursor was then directly hydrolyzed to obtain nanocrystalline NiO. The precursor was characterized by FTIR, HNMR, Raman spectra and the nano-powder was characterized by XRD and TEM. The results showed that the NiO powder after calcined at 450 ℃ had formed the cubic NaCl structure and the nanocrystalline NiO prepared by this method had narrow size distribution of 10～15 nm. Moreover, the product yield could be improved by controlling temperature below …

Morphologic And Magnetic Properties Of Pd₁₀₀₋ₓfeₓ Nanoparticles Prepared By Ultrasound Assisted Electrochemistry, Maribel Guzman, Jean Luc Delplancke, Gary J. Long, Jacques P. Delwiche, Marie Jeanne Hubin-Franskin, Fernande Grandjean

Chemistry Faculty Research & Creative Works

Nanopowdered alloys of Pd_100-xFe_x, with x=4, 6, 8, and 12, have been prepared by ultrasound assisted electrochemistry. The composition of the individual particles, as determined by x-ray fluorescence, and the bulk composition, as determined by atomic absorption, are in agreement within experimental error. Transmission electron microscopy indicates that the nanopowders consist of agglomerates of small grains with a radius of approximately 5 nm, a radius which is confirmed by the broadening of the reflections in the x-ray powder diffraction patterns. X-ray fluorescence analysis of individual grains indicates a homogeneous distribution of palladium and iron throughout the …

Application Of Electrochemical Techniques To The Researches In Life Science, Jian-Tao Pang, Chun-Hai Fan, Gen-Xi Li

Journal of Electrochemistry

The research work of our group in the last two years is briefly reviewed in this paper. By using electrochemical method, and combining some other chemical and biological techniques, lots of achievements have been obtained. And these researches are towards some hot topics in life science, such as function conversion, interaction between signal molecules and proteins, electron-transfer of biomolecules, gene detection, structural biology, biochemical analysis and the third generation biosensors.

Some Trends Of Electrochemistry In 21st Century, Zhong-Hua Lin

Journal of Electrochemistry

The important advances in electrochemistry in the late twentieth century are reviewed and some trends of electrochemistry in earlier stage of the twenty-first century are discussed. Future researches in electrochemistry are indicated with an emphasis being made on the electrochemistry in new systems.

Electrochemistry And Spectroscopy Of Sulfate And Thiosulfate Complexes Of Iron Porphyrins, Philip Walter Crawford, Michael D. Ryan

Chemistry Faculty Research and Publications

The electrochemical and spectroscopic properties of the complex formed by the addition of thiosulfate to ferric porphyrins were examined. The NMR spectrum of the thiosulfate–ferric porphyrin complex was consistent with a high-spin ferric complex, while the EPR spectrum at liquid nitrogen temperatures indicated that the complex under these conditions was low-spin. Such behavior has been previously observed for other ferric porphyrin complexes. The visible spectra were characterized by a shift in the Soret band to higher energies, with smaller changes in the longer wavelength region. The complex was reasonably stable in DMF, but slowly reduced over several hours to Fe …