A Comparison between Structural and Electrochemical Properties of Iridium Oxide-Based Electrocatalysts Prepared by Sol-Gel and Reactive Sputtering Deposition
| Autor: | Achille De Battisti, Valentino Rigato, Giancarlo Battaglin, Sergio Ferro, Davide Rosestolato, Stefano Neodo |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Sol-Gel
Materials science Inorganic chemistry Oxide chemistry.chemical_element DSA Physical vapor deposition Sol-Gel electrochemical activity iridium oxide DSA NO Corrosion chemistry.chemical_compound iridium oxide electrochemical activity Sputtering Materials Chemistry Electrochemistry rf-sputtering Iridium Renewable Energy Sustainability and the Environment Gas evolution reaction Oxygen evolution electrochemical properties Sputter deposition Condensed Matter Physics Surfaces Coatings and Films Electronic Optical and Magnetic Materials chemistry Physical vapor deposition Iridium oxide sol gel Titanium |
| Zdroj: | Journal of The Electrochemical Society. 161:E151-E158 |
| ISSN: | 1945-7111 0013-4651 |
| Popis: | The great interest of the electrochemical industry toward materials that exhibit high electrocatalytic activity and long service-life in electrolytic processes has constantly prompted fundamental research, enhancing the understanding of electrode behavior and the improvement of their performance. One of the most important class of industrial devices is represented by the so-called DSAs, which consist of an electrocatalytic oxide film (usually based on RuO2 and/or IrO2) deposited on a suitable metal support (titanium). To increase the stability of the material, other oxides (TiO2 ,S nO2, etc.) are added to the electrocatalytic one, with the double purpose of increasing the corrosion resistance of the coating and of diluting the main oxide (to minimize the production costs). In this work, mixtures of 35 mol% IrO2 ‐6 5 mol% TiO2 deposited on titanium supports have been studied by ex-situ (RBS, XRD, ERDA, AFM) and on-site (CV) techniques. Electrodes prepared by an updated sol-gel method and reactive sputtering, at two different temperatures (350 and 450 ◦ C), were investigated with the aim of correlating structural information with electrochemical performances, in terms of number of active electrocatalytic iridium sites. Based on roughness indexes, morphological properties, and of data obtained by nuclearmethodsforsurfaceanalysisandcyclicvoltammetry,thebehaviorofiridiumsiteshasbeendiscussed,attemptingaqualitative distinction of roles of roughness and intrinsic catalytic activity in a model-electrochemical reaction, like oxygen evolution reaction. Sputtered samples appear, in general, more compact than sol-gel ones, and a low temperature of pyrolysis favours a more extended electroactive surface. The study of OER demonstrates that the kinetics of gas evolution proceeds via the electrochemical oxide formation pathway (Volmer-Heyrovsky mechanism) on all samples. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|