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Electrochemical synthesis of CeO2 and CeO2/montmorillonite nanocomposites.

Description: Nanocrystalline cerium oxide thin films on metal and semiconductor substrates have been fabricated with a novel electrodeposition approach - anodic oxidation. X-ray diffraction analysis indicated that as-produced cerium oxide films are characteristic face-centered cubic fluorite structure with 5 ~ 20 nm crystal sizes. X-ray photoelectron spectroscopy study probes the non-stoichiometry property of as-produced films. Raman spectroscopy and Scanning Electron Microscopy have been applied to analyze the films as well. Deposition mode, current density, reaction temperature and pH have also been investigated and the deposition condition has been optimized for preferred oriented film formation: galvanostatic deposition with current density of -0.06 mA/cm2, T > 50oC and 7 < pH < 10. Generally, potentiostatic deposition results in random structured cerium oxide films. Sintering of potentiostatic deposited cerium oxide films leads to crystal growth and reach nearly full density at 1100oC. It is demonstrated that in-air heating favors the 1:2 stoichiometry of CeO2. Nanocrystalline cerium oxide powders (4 ~ 10 nm) have been produced with anodic electrochemical synthesis. X-ray diffraction and Raman spectroscopy were employed to investigate lattice expansion phenomenon related to the nanoscale cerium oxide particles. The pH of reaction solution plays an important role in electrochemical synthesis of cerium oxide films and powder. Cyclic voltammetry and rotation disk electrode voltammetry have been used to study the reaction mechanisms. The results indicate that the film deposition and powder formation follow different reaction schemes. Ce(III)-L complexation is a reversible process, Ce3+ at medium basic pH region (7~10) is electrochemically oxidized to and then CeO2 film is deposited on the substrate. CE mechanism is suggested to be involved in the formation of films, free Ce3+ species is coordinated with OH- at high basic pH region (>10) to Ce2O3 immediately prior to electrochemically oxidation Ce2O3 to CeO2. CeO2 / montmorillonite nanocomposites were electrochemically produced. X-ray ...
Date: December 2003
Creator: Wang, Qi
Partner: UNT Libraries

Electrochemical Dissolution of ZnO Single Crystals

Description: The separation of oxidation-reduction reactions into individual half-cells with a resulting "mixed potential" is well known as a dissolution mechanism for metals; however, the mechanism by which non-conducting crystals lose ions to the solution has been studied only slightly.
Date: January 1970
Creator: Justice, David Dixon
Partner: UNT Libraries

Copper Electrodeposition on Iridium, Ruthenium and Its Conductive Oxide Substrate

Description: The aim of this thesis was to investigate the physical and electrochemical properties of sub monolayer and monolayer of copper deposition on the polycrystalline iridium, ruthenium and its conductive oxide. The electrochemical methods cyclic voltammetry (CV) and chronocoulometry were used to study the under potential deposition. The electrochemical methods to oxidize the ruthenium metal are presented, and the electrochemical properties of the oxide ruthenium are studied. The full range of CV is presented in this thesis, and the distances between the stripping bulk peak and stripping UPD peak in various concentration of CuSO4 on iridium, ruthenium and its conductive oxide are shown, which yields thermodynamic data on relative difference of bonding strength between Cu-Ru/Ir atoms and Cu-Cu atoms. The monolayer of UPD on ruthenium is about 0.5mL, and on oxidized ruthenium is around 0.9mL to 1.0mL. The conductive oxide ruthenium presents the similar properties of ruthenium metal. The pH effect of stripping bulk peak and stripping UPD peak of copper deposition on ruthenium and oxide ruthenium was investigated. The stripping UPD peak and stripping bulk peak disappeared after the pH ≥ 3 on oxidized ruthenium electrode, and a new peak appeared, which means the condition of pH is very important. The results show that the Cl- , SO42- , Br- will affect the position of stripping bulk peak and stripping UPD peak: the stripping bulk peak will shift and decrease if the concentration of halide ions is increasing, and the monolayer of UPD will increase at the same time.
Date: December 2003
Creator: Huang, Long
Partner: UNT Libraries

Study of Ruthenium and Ruthenium Oxide's Electrochemical Properties and Application as a Copper Diffusion Barrier

Description: As a very promising material of copper diffusion barrier for next generation microelectronics, Ru has already obtained a considerable attention recently. In this dissertation, we investigated ruthenium and ruthenium oxide electrochemical properties and the application as a copper diffusion barrier. Cu under potential deposition (UPD) on the RuOx formed electrochemically was first observed. Strong binding interaction, manifesting by the observed Cu UPD process, exists between Cu and Ru as well as its conductive ruthenium oxide. Since UPD can be conformally formed on the electrode surface, which enable Ru and RuOx has a potential application in the next generation anode. The [Cl-] and pH dependent experiment were conducted, both of them will affect UPD Cu on Ru oxide. We also found the Cu deposition is thermodynamically favored on RuOx formed electrochemically. We have studied the Ru thin film (5nm) as a copper diffusion barrier. It can successfully block Cu diffusion annealed at 300 oC for 10min under vacuum, and fail at 450 oC. We think the silicidation process at the interface between Ru and Si. PVD Cu/Ru/Si and ECP Cu/Ru/Si were compared each other during copper diffusion study. It was observed that ECP Cu is easy to diffuse through Ru barrier. The function of RuOx in diffusion study on Cu/Ru/Si stack was discussed. In pH 5 Cu2+ solution, Ru and Pt electrochemical behavior were investigated. A sharp difference was observed compared to low pH value. The mechanism in pH 5 Cu2+ solution was interpreted. An interesting compound (posnjakite) was obtained during the electrochemical process. An appropriate formation mechanism was proposed. Also Cu2O was formed in the process. We found oxygen reduction reaction is a key factor to cause this phenomenon.
Date: August 2005
Creator: Zhang, Yibin
Partner: UNT Libraries

Electrodeposition of Copper on Ruthenium Oxides and Bimetallic Corrosion of Copper/Ruthenium in Polyphenolic Antioxidants

Description: Copper (Cu) electrodeposition on ruthenium (Ru) oxides was studied due to important implications in semiconductor industry. Ruthenium, proposed as the copper diffusion barrier/liner material, has higher oxygen affinity to form different oxides. Three different oxides (the native oxide, reversible oxide, and irreversible oxide) were studied. Native oxide can be formed on exposing Ru in atmosphere. The reversible and irreversible oxides can be formed by applying electrochemical potential. Investigation of Cu under potential deposition on these oxides indicates the similarity between native and reversible oxides by its nature of inhibiting Cu deposition. Irreversible oxide formed on Ru surface is rather conductive and interfacial binding between Cu and Ru is greatly enhanced. After deposition, bimetallic corrosion of Cu/Ru in different polyphenols was studied. Polyphenols are widely used as antioxidants in post chemical mechanical planarization (CMP). For this purpose, different trihydroxyl substituted benzenes were used as antioxidants. Ru, with its noble nature enhances bimetallic corrosion of Cu. Gallic acid (3,4,5 - trihydroxybenzoic acid) was chosen as model compound. A mechanism has been proposed and validity of the mechanism was checked with other antioxidants. Results show that understanding the chemical structure of antioxidants is necessary during its course of reaction with Cu.
Date: August 2007
Creator: Venkataraman, Shyam S.
Partner: UNT Libraries

Proceedings of the Symposium and Workshop on Advanced Battery Research and Design : March 22-24, 1976

Description: The idea for this meeting evolved from interest expressed by members of the Chicago Section of the Electrochemical Society in convening a symposium on the development of high-energy secondary batteries. The relevance of this subject is evidenced by the several research programs that have been initiated recently in the United States and Europe to develop advanced batteries for use as energy storage devices on electric utility networks and as power sources for electric automobiles.
Date: 1976?
Creator: Selman, J. Robert; Steunenberg, Robert K.; Barghusen, John J. & Howard, William G.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Post-Test Analyses of Aqueous Batteries Developed for Electric Propulsion : Summary Report for January 1985-September 1986

Description: This document is a summary of the activities conducted on post-test examination of aqueous electric-vehicle batteries from January 1985 to September 1986. The post-test analyses were conducted to determine the causes of performance degradation (e.g., capacity decline, power loss, self-discharge) in lead-acid and nickel/iron batteries. For the lead-acid batteries, the primary causes of capacity decline were generally found to be morphological changes in the positive active material, corrosion of the positive electrode grid, and loss of contact between the active material and grid in the positive electrode. For the nickel/iron batteries, the primary factors responsible for performance degradation were transport of iron through the separator to the nickel electrode and loss of contact between the active materials and current collector. These results have permitted more accurate assessments of current technical progress in development of aqueous electric-vehicle batteries and have helped to direct future R and D efforts.
Date: July 1987
Creator: Miller, J. F.; Marr, J. J. & Smaga, J. A.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Testing and Development of Electric Vehicle Batteries for EPRI Electric Transportation Program : Technical Report for January 1985 - April 1986

Description: The battery is a key element in the acceptance of electric vehicles, and R and D efforts are being undertaken to improve battery performance and lifetime. In this electric-vehicle battery program, controlled laboratory tests were conducted to evaluate the effects of selected factors on the performance and life of the EV-2300 lead-acid battery manufactured by Johnson Controls, Inc. These factors included simulated driving profiles with different levels of peak power demands for vehicle acceleration, long rest times after charge or discharge, and different methods of recharging. The performance and cycle life of a 12-module full-scale battery pack and its support system were also evaluated. This report summarizes the work carried out on this program from January 1985 through April 1986. This work involved tests of the battery pack and support system, statistical analysis of capacity and power data from earlier tests of six-cell modules, and post-test analysis of selected modules and cells.
Date: January 1988
Creator: Argonne National Laboratory
Item Type: Report
Partner: UNT Libraries Government Documents Department

Status of the Li-Al/FeS Battery Manufacturing Technology. Final Report. November 1983. An Evaluation for the US Army, Belvoir R and D Center

Description: Research and development work on rechargeable lithium/molten salt batteries, sponsored by the US Department of Energy, has been under way at Argonne National Laboratory and several industrial laboratories for the past decade. In 1978, a program for the US Army (Belvoir R and D Center) was initiated with ANL and Eagle-Picher Industries to ascertain the status and to aid the development of the manufacturing technology of the Li-Al/FeS battery as a power source for forklift trucks. A long-lived cell, achieving greater than 1000 discharge cycles, was developed in the Army program and was used as a basis for a forklift truck battery design. The projected performance of the Li-Al/FeS battery showed a 200% increase in stored energy when compared with a lead-acid battery of equal volume.
Date: August 1984
Creator: Chilenskas, A. A.; Shimotake, H.; Malecha, R.; Battles, J.; Miller, W.; Yao, N. P. et al.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Proceedings of the International Workshop on High-Temperature Molten Salt Batteries : April 16-18, 1986

Description: This three-day workshop on high-temperature molten salt batteries provided an excellent opportunity to bring together those who are actively involved in the research and development of rechargeable, molten-salt battery systems. Twenty-six papers are presented in three sessions, titled: basic properties of molten salt battery systems, engineering development of lithium-alloy/metal sulfide batteries; and research and development in molten salt systems. This format has been retained in the publication of the workshop papers, with each part having separate pagination.
Date: 1986
Creator: McLarnon, Frank
Item Type: Report
Partner: UNT Libraries Government Documents Department

Effect of Depth of Discharge on Lead-Acid Battery Overcharge Requirements

Description: Proper charging is essential to achieve maximum performance and life of lead-acid batteries. Excessive overcharging gives rise to increased battery temperature, gassing rates, electrolyte maintenance, and component corrosion, whereas repeated undercharging causes a gradual decrease in battery capacity, which often becomes irreversible. To develop an optimal charge procedure, the relation between battery available capacity, applied overcharge, and the depth-of-discharge (DOD) level prior to charging needed to be established.
Date: February 1986
Creator: DeLuca, W. H. & Tummillo, A. F.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Metal Corrosion Associated with Thermal Cycling of Inhibited and Uninhibited Propylene Glycol/Water Solution in Solar DHW Systems

Description: As part of the Solar Reliability and Materials Program at Argonne National Laboratory, metal corrosion associated with thermal cycling at 82 C circulating and 176 C stagnating temperatures of propylene glycol and ASTM corrosive water mixture (50% v/o) was investigated. Preliminary data indicate that in a mixed metal system of copper, steel, and aluminum specimens stagnating together in a glycol solution, the copper randomly pits and the pitting stops when the pit depth extends to about 1-1/2 mil. The addition of 1% molybdate as an inhibitor to the glycol solution is slightly beneficial for steel, but the added expense of adding and maintaining the concentration of an inhibitor may not be warranted. Dissolved copper rapidly deposits on the aluminum surface and promotes severe galvanic corrosion.
Date: April 1983
Creator: Cheng, Craig F.
Item Type: Report
Partner: UNT Libraries Government Documents Department

The Wetting Behavior of Molten-Chloride Electrolytes: Capillarity Effects in Lithium-Aluminum/Metal Sulfide Batteries

Description: A lithium-aluminum/iron sulfide battery which uses a molten LiCl-KCl electrolyte is presently under development at Argonne National Laboratory. The performance and lifetime of this electrochemical system depend, in part, on the ability of the electrolyte to wet the materials used as electrodes, separators, and particle retainers. For this reason contact-angle measurements were made on smooth, 100%-dense surfaces of the cell materials. In addition, electrolyte penetrability determinations were made on the porous materials actually used as cell separators and particle retainers. The results of these measurements led to techniques for completely filling porous cell components with electrolyte, suggestions for dealing with the problem of electrolyte creeping, estimates of the likelihood of electrolyte transfer from one porous component to another, and estimation of the maximum allowable vertical cell dimensions.
Date: August 1979
Creator: Eberhart, James G.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Effects of Operating Temperature on the Characteristics of Nickel/Iron Traction Batteries

Description: Performance of improved Ni/Fe electric vehicle batteries was measured at ambient temperatures of 0, 25, and 50 C for a range of overcharge levels, open-circuit stand times, and charge and discharge rates. Tests in which charges and discharges were performed at different battery operating temperatures showed that the discharge capacity of a Ni/Fe battery is directly related to its operating temperature, but its charge acceptance is decreased at 0 and 50 C by approx. 6% from that obtained at 25 C. The decline in battery efficiency at high temperatures is the result of increased self-discharge losses. In the first 0.5 h after charge, the Ah self-discharge loss at 50 C is twice (6%) that at 0 and 25 C (approx. 3%), corresponding to an increase in initial self-discharge rate from approx. 8 to 16 A. The increased self-discharge rate apparently occurs during the latter part of charging and, thereby, causes the 6% decline in charge acceptance. A decrease in battery efficiency also resulted at 50 C (6% coulombic and 4% energy efficiency loss) when the charge current was reduced from the 3-h to the 6-h rate. In comparison, low temperatures impact battery internal resistance and IR-free voltage more than high temperatures. For an increase in ambient temperature from 25 to 50 C, battery IR-free voltage increased less than 1% and battery resistance decreased only 3%. However, a decrease from 25 to 0 C resulted in a 2.3% decrease in IR-free voltage and about a 22% increase in resistance. The available capacity and operating efficiency of a Ni/Fe battery are maximal near 25 C. To maintain the same Ah capacity achieved at 25 C with a 20% overcharge, the overcharge must be doubled at 50 C (42%) and tripled at 0 C (60%). Test procedures and equipment are described, test data ...
Date: July 1986
Creator: DeLuca, W. H.; Biwer, R. L. & Tummillo, A. F.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Li-Alloy/FeS Cell Design and Analysis Report

Description: This report contains historical information on the Li-alloy/FeS system that will be useful in its future applications. This document includes the following: (1) the chemical and electrochemical reactions for the Li-alloy/FeS system, accomplishments in past cell development efforts, and performance attained by state-of-the-art cells vs performance goals; (2) detailed drawings of state-of-the-art cell designs, documentation of cell fabrication techniques, and comparisons of alternative types of cell components (such as BN felt vs MgO powder separators, stainless vs low-carbon steel cell housings) and fabrication techniques (such as charged vs uncharged electrodes); (3) results of post-test cell analyses, including cell failure mechanisms, electrode morphology and active material distribution, and in-cell corrosion rates; (4) data from trade-off studies between specific power and energy; (5) discussion of battery design considerations (e.g., volumetric energy density, battery charger, and high-efficiency thermal insulation); (6) results of cost studies, which include materials and manufacturing costs of cells and batteries and heating costs involved in battery operation; and (7) projections of cell designs having the greatest potential for meeting electric-vehicle performance requirements.
Date: July 1985
Creator: Gay, E. C.; Steunenberg, Robert K.; Miller, W. E.; Battles, J. E.; Kaun, T. D.; Martino, F. J. et al.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Calcium/metal Sulfide Battery Development Program. Progress Report, October 1979 - September 1980

Description: A Ca-Al-Si/FeS2 cell has been developed and has exhibited reasonably stable capacity through 3200 h of operation. This system is expected to be capable of meeting the ultimate performance goals (i.e., 160 W.h/kg) of this development program. Further tests of this cell system in the coming year will better define its ultimate performance capabilities.
Date: March 1981
Creator: Barney, Duane L.; Roche, M. F.; Preto, S. K.; Ross, L. E.; Otto, N. C. & Martino, F. J.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Low work function material development for the microminiature thermionic converter.

Description: Thermionic energy conversion in a miniature format shows potential as a viable, high efficiency, micro to macro-scale power source. A microminiature thermionic converter (MTC) with inter-electrode spacings on the order of microns has been prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes that can be integrated into these converters to increase power production at modest temperatures (800 - 1300 K). The electrode materials are not well understood and the electrode thermionic properties are highly sensitive to manufacturing processes. Advanced theoretical, modeling, and fabrication capabilities are required to achieve optimum performance for MTC diodes. This report describes the modeling and fabrication efforts performed to develop micro dispenser cathodes for use in the MTC.
Date: March 1, 2004
Creator: Zavadil, Kevin Robert; Battaile, Corbett Chandler; Marshall, Albert Christian; King, Donald Bryan & Jennison, Dwight Richard
Item Type: Report
Partner: UNT Libraries Government Documents Department

LIGA-based microsystem manufacturing:the electrochemistry of through-mold depostion and material properties.

Description: The report presented below is to appear in ''Electrochemistry at the Nanoscale'', Patrik Schmuki, Ed. Springer-Verlag, (ca. 2005). The history of the LIGA process, used for fabricating dimensional precise structures for microsystem applications, is briefly reviewed, as are the basic elements of the technology. The principal focus however, is on the unique aspects of the electrochemistry of LIGA through-mask metal deposition and the generation of the fine and uniform microstructures necessary to ensure proper functionality of LIGA components. We draw from both previously published work by external researchers in the field as well as from published and unpublished studies from within Sandia.
Date: June 1, 2005
Creator: Kelly, James J. (Sandia National Laboratories, Livermore, CA) & Goods, Steven Howard (Sandia National Laboratories, Livermore, CA)
Item Type: Report
Partner: UNT Libraries Government Documents Department

Ion Replacement Program Annual Report: 1993

Description: Annual report of the Ion Replacement Electrorefining Program at Aronne National Laboratory describing their research and activities. There are three key accomplishments highlighted for the year: (1) identification of a suitable sodium(beta){double_prime}-alumina/molten salt electrolyte system that functions reproducibly at 723 K, (2) actual separation of dysprosium and lanthanum in experiments, and (3) the identification of a metal alloy, Li{sub x}Sb, as an alternative ion replacement electrode.
Date: July 1993
Creator: Tomczuk, Z.
Item Type: Report
Partner: UNT Libraries Government Documents Department

Cu Electrodeposition on Ru with a Chemisorbed Iodine Surface Layer.

Description: An iodine surface layer has been prepared on Ru(poly) and Ru(0001) electrodes by exposure to iodine vapor in UHV and polarizing in a 0.1 M HClO4/0.005 M KI solution, respectively. A saturation coverage of I on a Ru(poly) electrode passivates the Ru surface against significant hydroxide, chemisorbed oxygen or oxide formation during exposure to water vapor over an electrochemical cell in a UHV-electrochemistry transfer system. Immersion of I-Ru(poly) results in greater hydroxide and chemisorbed oxygen formation than water vapor exposure, but an inhibition of surface oxide formation relative that of the unmodified Ru(poly) surface is still observed. Studies with combined electrochemical and XPS techniques show that the iodine surface adlayer remained on top of the surface after cycles of overpotential electrodeposition/dissolution of copper on both Ru(poly) and Ru(0001) electrodes. These results indicate the potential bifunctionality of iodine layer to both passivate the Ru surface in the microelectronic processing and to act as a surfactant for copper electrodeposition. The electrodeposition of Cu on Ru(0001) or polycrystalline Ru was studied using XPS with combined ultrahigh vacuum/electrochemistry methodology (UHV-EC) in 0.1 M HClO4 with Cu(ClO4)2 concentrations ranging from 0.005 M to 0.0005 M, and on polycrystalline Ru in a 0.05M H2SO4/0.005 M CuSO4/0.001 M NaCl solution. The electrochemical data show well-defined cyclic voltammograms (CV) with a Cu underpotential deposition (UPD) peak and overpotential deposition (OPD) peak. XPS spectra of Ru electrodes emersed from perchloric acid solution at cathodic potentials indicate that ClO4- anions dissociate to yield specifically adsorbed Cl and ClOx species. Subsequent Cu deposition results in the formation of a thin, insoluble Cu(II) film with Cu(I) underneath. In contrast, similar deposition on polycrystalline Ru in the sulfuric acid/Cu sulfate solution with NaCl added yields only Cu(0), indicating that the formation of Cu(II) and Cu(I) involves both Cl and perchlorate interactions with the ...
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Date: August 2005
Creator: Lei, Jipu
Partner: UNT Libraries