Nanostructured Catalytic Electrodes for Low-Temperature Fuel Cells: Activation of Reactive Sites through Modification with Ultra-Thin Films of Metal Oxo Species
| Autor: | Roberto Marassi, Artur Zurowski, Pawel J. Kulesza, Aneta Kolary-Zurowska |
|---|---|
| Rok vydání: | 2010 |
| Předmět: | |
| Zdroj: | ECS Transactions. 33:131-142 |
| ISSN: | 1938-6737 1938-5862 |
| DOI: | 10.1149/1.3484510 |
| Popis: | We describe a new preparation method for preparation of a stable water-insoluble composite film containing platinum nanoparticles dispersed in conductive high-surface-area zeolite-type matrices of Vulcan XC-72 carbon supported acidic salts of cesium phosphododecatungstate (Cs2.5 H0.5PW12O40). To obtain the composite, Pt is obtained through corrosion of a Pt flag counter electrode (in 0.5 moldm-3 H2SO4/5 mmol dm-3 KCl using cycling voltammetry) and deposited on the working electrode (glassy carbon) substrate modified with Cs2.5H0.5PW12O40 mixed with Vulcan XC-72 carbon nanoparticles. For comparison, we also have considered the working electrode modified with Vulcan (XC-72) carbon nanoparticles. High resolution transmission electron microscopy (HRTEM) has been utilized to investigate dispersion platinum nanoparticles deposited on the polyoxometallate matrix. CO-stripping voltammetry has been used to determine the Pt surface area in the catalytic layer. The results have shown high electrocatalytic activity of the electrode containing low loading of Pt nanoparticles (about 2.6 μg cm-2 and of the size 1-2 nm) towards oxygen reduction. It is expected that Pt is located inside pores of zeolitic Cs2.5H0.5PW12O40. The electrochemical behavior of the Cs2.5H0.5PW12O40 salt has been asessed using cycling voltammetry. Reactivity of Pt-free Cs2.5H0.5PW12O40 system towards reduction of hydrogen peroxide (i. e., the undesirable oxygen reduction intermediate) has also been addressed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|