Incorporation of RuSex/C within nanostructural Ir matrices to enhance oxygen reduction

Beata Baranowska ,  Hanna Elzanowska ,  Magdalena Skunik ,  Paweł J. Kulesza 

Warsaw University, Faculty of Chemistry, Pasteura 1, Warszawa 02-093, Poland


One of the main aims of the research on fuel cells is creating the most efficient electrocatalysts for oxygen reduction. The platinum based catalysts have been so far most commonly used systems for cathodes. However the problem is the high activity of Pt towards methanol oxidation, which reduces possibility of its using as cathode in Direct Methanol Fuel Cells (DMFCs) in which methanol crossover through the polymer membrane from the anode to the cathode can occur. Direct reaction of a fuel with catalyst at the cathode leads to its depolarization and to the drop of the cell power. An interesting alternative to Pt-based catalysts in DMFCs can be RuSex nanoparticles, because of it’s high methanol tolerance. But to make system more attractive, the potential of the oxygen reduction should be shifted towards more positive values. This feature has been recently achieved by us via modification of carbon-supported RuSex nanoparticles with ultra-thin films of tungsten oxide (WO3).
In this work we utilize the iridium nanoparticles (obtained by sol-gel method) as the addition to RuSex/C catalyst. Ir surface can be partially oxidized during potential cycling and as a result the mixture of Ir with mixed valent oxides (IrOx) is formed. Ir oxides are characterized by good electronic conductivity, the property necessary to enhance O2 reduction. Apart from that, just like in the case of WO3, iridium structures are highly active towards hydrogen peroxide reduction, thus supporting direct reduction of oxygen to water. The TEM images illustrate that nanostructural Ir makes compact polymeric type structure analogous to those previously observed for WO3. It is reasonable to expect that IrOx may serve as a matrix for carbon-supported RuSex particles. Analysis of voltammetric and RDE experiments shows that, after modification of RuSex by iridium nanoparticles, better catalytic properties of the cathode, namely the positive shift of the reaction potential and the increase of the reaction rate (in comparison to bare RuSex and Ir/IrOx systems) have been obtained.

Legal notice
  • Legal notice:

    Copyright (c) Pielaszek Research, all rights reserved.
    The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
    In every case, proper references including Author(s) name(s) and URL of this webpage: must be provided.


Related papers
  1. Detection of supercoiled and linear plasmid DNA
  2. Development of multifunctional bioelectrocatalytic films for oxidation of ethanol   
  3. The interactions between methylene blue and various types of DNA at screen-printed electrodes
  4. Integrated carbon nanotube based mediating systems for bioelectrocatalysis: application to oxygen reduction and glucose oxidation
  5. Preparation of copper hexacyanoferrate multilayer films modified with 4-(Pyrrole-1-yl) benzoic acid on glassy carbon electrode.
  6. Development of electrocatalytic materials based on the mixed addenda Dawson heteropolyanion and conducting polymers
  7. Development of novel bioelectrocatalytic systems through controlled combination of multiwalled carbon nanotubes, redox mediators and enzymes
  8. Oxidation of glucose at nanostructured composite bioelectrocatalytic systems
  9. Application of Inorganic Redox - Conducting Solids As Charge Relays in Dye-Sensitized Solar Cell
  10. Bi-functional electrocatalytic systems for oxygen reduction in acid medium
  11. Electrochemical charging of carbon nanotubes modified with polyoxometallates monolayers
  12. Enzymatic carbon nanotube based composite electrodes for dioxygen reduction
  13. Multifunctional bio-electrocatalytic systems for reduction of oxygen and hydrogen peroxide
  14. Electrocatalysis and Bioelectrocatalysis at Network Films of Metal Nanoparticles and Carbon Nanostructures
  15. Bioelectrocatalytic dioxygen reduction at carbon nanotubes – silicate composite film modified electrode
  16. Development and characterization of bioelectrocatalytic systems for oxygen reduction
  17. Activation of Methanol-Tolerant Carbon-Supported RuSex Electrocatalytic Nanoparticles Towards More Efficient Oxygen Reduction
  18. Electrocatalysis and bioelectrocatalysis and nanostructured composite films
  19. Some electrochemical properties of laccase immobilised on the Au, IrOx, or C60-Pd polymer electrode supports
  20. New strategies in the electroctalytic reduction of oxygen for fuel and biofuel cells
  21. Polyoxometallate-modified conducting polymer linked Pt nanoparticles as bifunctional electrocatalysts for bromate reduction
  22. Network Films of Conducting Polymer Linked and Polymeatallate Stabilized Platinum Nanoparticles

Presentation: Poster at SMCBS'2007 International Workshop, by Beata Baranowska
See On-line Journal of SMCBS'2007 International Workshop

Submitted: 2007-09-25 16:23
Revised:   2009-06-07 00:48
© 1998-2021 pielaszek research, all rights reserved Powered by the Conference Engine