Patents by Inventor Thomas A. Zawodzinski

Thomas A. Zawodzinski has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11031606
    Abstract: An electrochemical cell includes an air electrode in flow communication with a storage tank containing an aqueous solution of hydrogen peroxide, a lithium electrode, a catalyst layer in contact with the air electrode or a gas diffusion layer associated with the air electrode, and a separator layer in contact with the lithium electrode and catalyst layer. The catalyst layer includes a catalyst for two electron reversible oxygen reduction. The catalyst comprises gold, and a cobalt coordination complex or polymer thereof. The cobalt coordination complex comprises a cobalt ion chelated by a tetradentate organic chelating ligand.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: June 8, 2021
    Assignee: University of Tennessee Research Foundation
    Inventors: Ming Qi, Thomas Zawodzinski, Shane Foister
  • Publication number: 20200168915
    Abstract: An electrochemical cell includes an air electrode in flow communication with a storage tank containing an aqueous solution of hydrogen peroxide, a lithium electrode, a catalyst layer in contact with the air electrode or a gas diffusion layer associated with the air electrode, and a separator layer in contact with the lithium electrode and catalyst layer. The catalyst layer includes a catalyst for two electron reversible oxygen reduction. The catalyst comprises gold, and a cobalt coordination complex or polymer thereof. The cobalt coordination complex comprises a cobalt ion chelated by a tetradentate organic chelating ligand.
    Type: Application
    Filed: November 22, 2019
    Publication date: May 28, 2020
    Inventors: Ming Qi, Thomas Zawodzinski, Shane Foister
  • Patent number: 10522842
    Abstract: A catalyst is provided for the two electron reduction of oxygen. The catalyst can be reversible or near-reversible. The catalyst comprises a gold and a cobalt coordination complex, i.e., N,N?-bis(salicylidene)ethylene-diaminocobalt (II) (cobalt salen) or a derivative thereof. The cobalt coordination complex can be polymerized to form a film, for example, via electropolymerization, to cover a gold surface. Also provided are metal-air batteries, fuel cells, and air electrodes that comprise the catalyst, as well as methods of using the catalyst, for example, to reduce oxygen and/or produce hydrogen peroxide.
    Type: Grant
    Filed: November 3, 2014
    Date of Patent: December 31, 2019
    Assignee: University of Tennessee Research Foundation
    Inventors: Ming Qi, Thomas Zawodzinski, Shane Foister
  • Publication number: 20190168170
    Abstract: An electrochemical device includes an anode, a cathode, and a separator interposed between the anode and cathode. The separator includes an anion conductive membrane having a porous substrate having hydrophilic moieties bonded thereto to increase water availability in a vicinity of ionogenic sites contributing to conductivity of the membrane in a presence of aqueous phases imbibed therein.
    Type: Application
    Filed: July 27, 2017
    Publication date: June 6, 2019
    Applicant: UNIVERSITY OF TENNESSEE RESEARCH FOUNDATION
    Inventors: Thomas ZAWODZINSKI, Shane FOISTER
  • Publication number: 20160308220
    Abstract: A catalyst is provided for the two electron reduction of oxygen. The catalyst can be reversible or near-reversible. The catalyst comprises a gold and a cobalt coordination complex, i.e., N,N?-bis(salicylidene)ethylene-diaminocobalt (II) (cobalt salen) or a derivative thereof. The cobalt coordination complex can be polymerized to form a film, for example, via electropolymerization, to cover a gold surface. Also provided are metal-air batteries, fuel cells, and air electrodes that comprise the catalyst, as well as methods of using the catalyst, for example, to reduce oxygen and/or produce hydrogen peroxide.
    Type: Application
    Filed: November 3, 2014
    Publication date: October 20, 2016
    Inventors: Ming QI, Thomas ZAWODZINSKI, Shane FOISTER
  • Publication number: 20150072261
    Abstract: An electrochemical flow type battery may include at least one electrode and a separator. The electrode may include carbon fibers and/or carbon particles, and has an internal surface area density of at least 1 m2/g. The separator may separate an anode side and a cathode side of the battery. A flat surface of the electrode directly contacts a surface of the separator.
    Type: Application
    Filed: November 8, 2013
    Publication date: March 12, 2015
    Inventors: Matthew Mench, Thomas Zawodzinski, Che-Nan Sun
  • Patent number: 6818341
    Abstract: A polymer electrolyte fuel cell (PEFC) is designed to operate on a reformate fuel stream containing oxygen and diluted hydrogen fuel with CO impurities. A polymer electrolyte membrane has an electrocatalytic surface formed from an electrocatalyst mixed with the polymer and bonded on an anode side of the membrane. An anode backing is formed of a porous electrically conductive material and has a first surface abutting the electrocatalytic surface and a second surface facing away from the membrane. The second surface has an oxidation catalyst layer effective to catalyze the oxidation of CO by oxygen present in the fuel stream where at least the layer of oxidation catalyst is formed of a non-precious metal oxidation catalyst selected from the group consisting of Cu, Fe, Co, Tb, W, Mo, Sn, and oxides thereof, and other metals having at least two low oxidation states.
    Type: Grant
    Filed: May 3, 2001
    Date of Patent: November 16, 2004
    Assignee: The Regents of the University of California
    Inventors: Francisco A. Uribe, Thomas A. Zawodzinski
  • Patent number: 6635369
    Abstract: A method is provided for operating a fuel cell at high voltage for sustained periods of time. The cathode is switched to an output load effective to reduce the cell voltage at a pulse width effective to reverse performance degradation from OH adsorption onto cathode catalyst surfaces. The voltage is stepped to a value of less than about 0.6 V to obtain the improved and sustained performance.
    Type: Grant
    Filed: May 22, 2001
    Date of Patent: October 21, 2003
    Assignee: The Regents of the University of California
    Inventors: Francisco A. Uribe, Thomas Zawodzinski
  • Publication number: 20020119363
    Abstract: A polymer electrolyte fuel cell (PEFC) is designed to operate on a reformate fuel stream containing oxygen and diluted hydrogen fuel with CO impurities. A polymer electrolyte membrane has an electrocatalytic surface formed from an electrocatalyst mixed with the polymer and bonded on an anode side of the membrane. An anode backing is formed of a porous electrically conductive material and has a first surface abutting the electrocatalytic surface and a second surface facing away from the membrane. The second surface has an oxidation catalyst layer effective to catalyze the oxidation of CO by oxygen present in the fuel stream where at least the layer of oxidation catalyst is formed of a non-precious metal oxidation catalyst selected from the group consisting of Cu, Fe, Co, Tb, W, Mo, Sn, and oxides thereof, and other metals having at least two low oxidation states.
    Type: Application
    Filed: May 3, 2001
    Publication date: August 29, 2002
    Inventors: Francisco A. Uribe, Thomas A. Zawodzinski
  • Publication number: 20010044040
    Abstract: A method is provided for operating a fuel cell at high voltage for sustained periods of time. The cathode is switched to an output load effective to reduce the cell voltage at a pulse width effective to reverse performance degradation from OH adsorption onto cathode catalyst surfaces. The voltage is stepped to a value of less than about 0.6 V to obtain the improved and sustained performance.
    Type: Application
    Filed: May 22, 2001
    Publication date: November 22, 2001
    Inventors: Francisco A. Uribe, Thomas Zawodzinski
  • Patent number: 5227042
    Abstract: An enzyme electrode is prepared with a composite coating on an electrical conductor. The composite coating is formed from a casting solution of a perfluorosulfonic acid polymer, an enzyme, and a carbon supported catalyst. The solution may be cast directly on the conductor surface or may be formed as a membrane and applied to the surface. The perfluorosulfonic acid ionomer formed from the casting solution provides an insoluble biocompatible protective matrix for the enzyme and acts to retain the enzyme for long term availability in the electrode structure. The carbon supported catalyst provides catalytic sites throughout the layer for the oxidation of hydrogen peroxide from the enzyme reactions. The carbon support then provides a conductive path for establishing an electrical signal to the electrical conductor.
    Type: Grant
    Filed: May 15, 1992
    Date of Patent: July 13, 1993
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Thomas A. Zawodzinski, Mahlon S. Wilson, Judith Rishpon, Shimshon Gottesfeld
  • Patent number: 5082550
    Abstract: An electrochemical sensor electrode is formed from an electronic conductor coated with a casting solution containing a perfluorosulfonic acid ionomer and a selected enzyme. The selected enzyme catalyzes a reaction between a predetermined substance in a solution and oxygen to form an electrochemically active compound that is detected at the electronic conductor. The resulting perfluorosulfonic acid polymer provides a stable matrix for the enzyme for long lived enzyme activity, wherein only thin coatings are required on the metal conductor. The polymer also advantageously repels interfering substances from contacting the enzyme and contains quantities of oxygen to maintain a sensing capability during conditions of oxygen depletion in the sample. In one particular embodiment, glucose oxidase is mixed with the perfluorosulfonic acid ionomer to form an electrode for glucose detection.
    Type: Grant
    Filed: December 11, 1989
    Date of Patent: January 21, 1992
    Assignee: The United States of America as represented by the Department of Energy
    Inventors: Judith Rishpon, Thomas A. Zawodzinski, Shimshon Gottesfeld