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New Catalysts for Direct Methanol Oxidation Fuel Cells

Description: A new class of efficient electrocatalytic materials based on platinum - metal oxide systems has been synthetized and characterized by several techniques. Best activity was found with NiWO{sub 4}-, CoWO{sub 4}-, and RuO{sub 2}- sr¡pported platinum catalysts. A very similar activity at room temperature was observed with the electrodes prepared with the catalyst obtained from International Fuel Cells Inc. for the same Pt loading. Surprisingly, the two tungstates per se show a small activity for methanol oxidation without any Pt loading. Synthesis of NiWO{sub 4} and CoWO{sub 4} were carried out by solid-state reactions. FTIR spectroscopy shows that the tungstates contain a certain amount of physically adsorbed water even after heating samples at 200{degrees}C. A direct relationship between the activity for methanol oxidation and the amount of adsorbed water on those oxides has been found. The Ru(0001) single crystal shows a very small activity for CO adsorption and oxidation, in contrast to the behavior of polycrystalline Ru. In situ extended x-ray absorption fine structure spectroscopy (EXAFS) and x-ray absorption near edge spectroscopy (XANES) showed that the OH adsorption on Ru in the Pt-Ru alloy appears to be the limiting step in methanol oxidation. This does not occur for Pt-RuO{SUB 2} electrocatalyst, which explains its advantages over the Pt-Ru alloys. The IFCC electrocatalyst has the properties of the Pt-Ru alloy.
Date: August 1, 1998
Creator: Adzic, Radoslav
Partner: UNT Libraries Government Documents Department

Seawater Softening by Ion Exchange as a Saline Water Conversion Pretreatment

Description: From Introduction: "A pilot plant embodying these ideas, in an unusual method of softening, was designed and constructed by the Texas Division of The Dow Chemical Company. Two 4,000 gallon per day vapor compression evaporators were furnished for the testing program bu the Bureau of Yards and Docks of the United States Navy. This report summarizes the results of the testing program."
Date: May 1962
Creator: McIlhenny, W. F.
Partner: UNT Libraries Government Documents Department

A Study of Large Size Saline Water Conversion Plants

Description: From Introduction: "The principal objective of this study is to digest the experience accumulated in the operation of the demonstration plants, and from this information, to arrive at the cost of fresh water when produced on a large scale. It is important to recognize that the costs, as calculated in this report, are based upon the state of development of the processes as exemplified and proven in the demonstration plants. The field is new, and the rate of development is such that further cost reductions may be expected."
Date: March 1963
Creator: Bechtel Corporation
Partner: UNT Libraries Government Documents Department

Research on Saline Water Conversion by Freezing

Description: From Introduction: "Progress of research related to problems encountered in processes for desalination by freezing is summarized in this report, which is the first annual progress report called for under the terms of Grant 14-01-0001-295 made to the Massachusetts Institute of Technology by the Office of Saline Water in 1962."
Date: March 1964
Creator: Sherwood, T. K. & Brian, P. L. T.
Partner: UNT Libraries Government Documents Department

Nanostructured Catalyst Systems for Fuel Cells: Synthesis and Characterization of Low Platinum Content Electrocatalysts for O{sub 2} Reduction

Description: The objective of this project is to synthesize and characterize new O{sub 2} reduction catalysts with enhanced activity and ultra low Pt loading, and to test them in membrane electrode assemblies (MEAs) to determine their performance under fuel cell cathode operating conditions.
Date: February 1, 2007
Creator: Adzic, Radoslav
Partner: UNT Libraries Government Documents Department

Manufacturing Cost Analysis for YSZ-Based FlexCells at Pilot and Full Scale Production Scales

Description: Significant reductions in cell costs must be achieved in order to realize the full commercial potential of megawatt-scale SOFC power systems. The FlexCell designed by NexTech Materials is a scalable SOFC technology that offers particular advantages over competitive technologies. In this updated topical report, NexTech analyzes its FlexCell design and fabrication process to establish manufacturing costs at both pilot scale (10 MW/year) and full-scale (250 MW/year) production levels and benchmarks this against estimated anode supported cell costs at the 250 MW scale. This analysis will show that even with conservative assumptions for yield, materials usage, and cell power density, a cost of $35 per kilowatt can be achieved at high volume. Through advancements in cell size and membrane thickness, NexTech has identified paths for achieving cell manufacturing costs as low as $27 per kilowatt for its FlexCell technology. Also in this report, NexTech analyzes the impact of raw material costs on cell cost, showing the significant increases that result if target raw material costs cannot be achieved at this volume.
Date: May 1, 2011
Creator: Swartz, Scott; Thrun, Lora; Kimbrell, Robin & Chenault, Kellie
Partner: UNT Libraries Government Documents Department

Validation of Novel Planar Cell Design for MW-Scale SOFC Power Systems

Description: This report describes the work completed by NexTech Materials, Ltd. during a three-year project to validate an electrolyte-supported planar solid oxide fuel cell design, termed the FlexCell, for coal-based, megawatt-scale power generation systems. This project was focused on the fabrication and testing of electrolyte-supported FlexCells with yttria-stabilized zirconia (YSZ) as the electrolyte material. YSZ based FlexCells were made with sizes ranging from 100 to 500 cm{sup 2}. Single-cell testing was performed to confirm high electrochemical performance, both with diluted hydrogen and simulated coal gas as fuels. Finite element analysis modeling was performed at The Ohio State University was performed to establish FlexCell architectures with optimum mechanical robustness. A manufacturing cost analysis was completed, which confirmed that manufacturing costs of less than $50/kW are achievable at high volumes (500 MW/year). DISCLAIMER
Date: September 30, 2011
Creator: Swartz, Scott; Thrun, Lora; Arkenberg, Gene & Chenault, Kellie
Partner: UNT Libraries Government Documents Department

SISGR: Theoretically relating the surface composition of Pt alloys to their performance as the electrocatalysts of low-temperature fuel cells

Description: The main goal of this project is to gain fundamental knowledge about the relation between surface composition and catalytic performance of Pt alloy catalysts for oxygen reduction reaction (ORR). Specific objectives are: to develop and improve a first-principles based multiscale computation approach to simulating surface segregation phenomena in Pt alloy surfaces; to evaluate the surface electronic structure and catalytic activity of Pt alloy catalysts and; to relate the surface composition to the catalytic performance of Pt alloy catalysts.
Date: December 31, 2010
Creator: Wang, Guofeng
Partner: UNT Libraries Government Documents Department

Qualification of primary loop manifold of a liquid metal thermoelectric converter

Description: The mechanical cycling test was required to verify the integrity of the welded joints and the thin wall tube bends in the primary loop manifold assembly of a four pack thermo electric module and to help establish structural and mechanical requirements of any possible redesign. The test section was subjected to more severe loading conditions than will be experienced during actual operating conditions. The test was a mechanical simulation of the differential thermal expansion which occurs due to the approximately 600{degrees} F temperature differential in the subassembly. The actual load exerted on the test section represented this deflection. The effects on the joints and tube material were observed. The test was conducted on a test segment of manifold designed to duplicate two of the flexible elbows; the transition joints between the elbows and the tubular module inner clad; and the welded joints of the elbows to the primary loop header. The assembled test segment and hold-down bracket are shown. The bracket was mounted to the base of the Universal Test Machine. Dial indicators measured the relative displacement between the line of applied load (through the vertical axis of the primary loop header) and the attachment point at the holddown bracket. In the first test, the load was applied in fifty pound increments until the relative displacement of nine mils was measured between the loop header and the welded joint on the feedline elbow. The remaining tests were cycling the header assembly at increasing relative displace ment. The summary of these tests are tabulated. The testing had no noticeable affect on the structural integrity of the weldment.
Date: June 10, 1969
Creator: Bryant, E P; Cottam, A E; Ettenson, N J; Harves, T O; Kenney, J; Letchford, T A et al.
Partner: UNT Libraries Government Documents Department

Innovative Self-Healing Seals for Solid Oxide Fuel Cells (SOFC)

Description: Solid oxide fuel cell (SOFC) technology is critical to several national initiatives. Solid State Energy Conversion Alliance (SECA) addresses the technology needs through its comprehensive programs on SOFC. A reliable and cost-effective seal that works at high temperatures is essential to the long-term performance of the SOFC for 40,000 hours at 800°C. Consequently, seals remain an area of highest priority for the SECA program and its industry teams. An innovative concept based on self-healing glasses was advanced and successfully demonstrated through seal tests for 3000 hours and 300 thermal cycles to minimize internal stresses under both steady state and thermal transients for making reliable seals for the SECA program. The self-healing concept requires glasses with low viscosity at the SOFC operating temperature of 800°C but this requirement may lead to excessive flow of the glass in areas forming the seal. To address this challenge, a modification to glass properties by addition of particulate fillers is pursued in the project. The underlying idea is that a non-reactive ceramic particulate filler is expected to form glass-ceramic composite and increase the seal viscosity thereby increasing the creep resistance of the glass-composite seals under load. The objectives of the program are to select appropriate filler materials for making glass-composite, fabricate glass-composites, measure thermal expansion behaviors, and determine stability of the glass-composites in air and fuel environments of a SOFC. Self-healing glass-YSZ composites are further developed and tested over a longer time periods under conditions typical of the SOFCs to validate the long-term stability up to 2000 hours. The new concepts of glass-composite seals, developed and nurtured in this program, are expected to be cost-effective as these are based on conventional processing approaches and use of the inexpensive materials.
Date: June 30, 2012
Creator: Singh, Raj
Partner: UNT Libraries Government Documents Department

How to Store Energy Fast

Description: Representing the Molecularly Engineered Energy Materials (MEEM), this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE energy. The mission of MEEM, using inexpensive custom-designed molecular building blocks, aims to create revolutionary new materials with self-assembled multi-scale architectures that will enable high performing energy generation and storage applications.
Date: July 18, 2013
Creator: Augustyn, Veronica; Ko, Jesse & Rauda, Iris
Partner: UNT Libraries Government Documents Department

Controlling Light to Make the Most Energy From the Sun

Description: Representing the Light-Material Interactions in Energy Conversion (LMI), this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE energy. The mission of LMI to tailor the morphology, complex dielectric structure, and electronic properties of matter so as to sculpt the flow of sunlight and heat, enabling light conversion to electrical and chemical energy with unprecedented efficiency.
Date: July 18, 2013
Creator: Callahan, Dennis; Corcoran, Chris; Eisler, Carissa; Flowers, Cris; Goodman, Matt; Hofmann, Carrie et al.
Partner: UNT Libraries Government Documents Department

Impact of HFIR LEU Conversion on Beryllium Reflector Degradation Factors

Description: An assessment of the impact of low enriched uranium (LEU) conversion on the factors that may cause the degradation of the beryllium reflector is performed for the High Flux Isotope Reactor (HFIR). The computational methods, models, and tools, comparisons with previous work, along with the results obtained are documented and discussed in this report. The report documents the results for the gas and neutronic poison production, and the heating in the beryllium reflector for both the highly enriched uranium (HEU) and LEU HFIR configurations, and discusses the impact that the conversion to LEU may have on these quantities. A time-averaging procedure was developed to calculate the isotopic (gas and poisons) production in reflector. The sensitivity of this approach to different approximations is gauged and documented. The results show that the gas is produced in the beryllium reflector at a total rate of 0.304 g/cycle for the HEU configuration; this rate increases by ~12% for the LEU case. The total tritium production rate in reflector is 0.098 g/cycle for the HEU core and approximately 11% higher for the LEU core. A significant increase (up to ~25%) in the neutronic poisons production in the reflector during the operation cycles is observed for the LEU core, compared to the HEU case, for regions close to the core s horizontal midplane. The poisoning level of the reflector may increase by more than two orders of magnitude during long periods of downtime. The heating rate in the reflector is estimated to be approximately 20% lower for the LEU core than for the HEU core. The decrease is due to a significantly lower contribution of the heating produced by the gamma radiation for the LEU core. Both the isotopic (gas and neutronic poisons) production and the heating rates are spatially non-uniform throughout the beryllium reflector volume. ...
Date: October 1, 2013
Creator: Ilas, Dan
Partner: UNT Libraries Government Documents Department

Fuel Cell Research at the University of South Carolina

Description: Five projects are proposed, in an effort to supplement the efforts of fuel cell research at the University of South Carolina and to contribute to the Technical Plan for Fuel Cells of the Department of Energy. These efforts include significant interaction with the industrial community through DOE funded projects and through the National Science Foundation’s Industry/University Cooperative Research Center for Fuel Cells. The allocation of projects described below leverage all of these sources of funding without overlap and redundancy. The first project “Novel Non-Precious Metal Catalyst For PEMFCs,” (Dr. Branko Popov) continues DOE award DE-FC36-03GO13108 for which funding was delayed by DOE due to budget constraints. The purpose of this project is to develop an understanding of the feasibility and limitations of metal-free catalysts. The second project, “Non Carbon Supported Catalysts” (Dr. John Weidner), is focused on improved catalysts and seeks to develop novel materials, which are more corrosion resistant. This corrosion behavior is critical during transient operation and during start-up and shutdown. This second project will be leveraged with recent, peer-reviewed, supplemental funding from NSF for use in the National Science Foundation Industry/University Cooperative Research Center for Fuel Cells (CFC) at USC. The third project, “Hydrogen Quality,” (Dr. Jean St-Pierre) will support the cross-program effort on H2 quality and focus on supporting subteam 1. We assume this task because of we have performed experiments and developed models that describe performance losses associated with CO, NH3, H2S contaminants in the hydrogen fuel feed to laboratory-scale single cells. That work has been focused on reformate fed to a stationary PEMFC and relatively high concentrations of these contaminants, this project will seek to apply that knowledge to the issue of hydrogen fuel quality as it relates to transportation needs. As part of this project USC and Oak Ridge National Laboratory (ORNL) will ...
Date: September 25, 2006
Creator: Van Zee, John W.
Partner: UNT Libraries Government Documents Department