| Autor: |
Liu, Hansan, Zhang, Lei, Zhang, Jiujun, Ghosh, Dave, Jung, Joey, Downing, Bruce W., Whittemore, Earl |
| Jazyk: |
angličtina |
| Rok vydání: |
2006 |
| Předmět: |
|
| DOI: |
10.1016/j.jpowsour.2006.04.132 |
| Popis: |
In this paper, the mechanism and kinetics of oxygen and hydrogen peroxide electrochemical reduction that is catalyzed by an adsorbed cobalt tetramethoxyphenyl porphyrin (CoTMPP) on a graphite electrode were investigated using cyclic voltammetry (CV) and the rotating disk electrode (RDE) technique. The temperature and anion effects on O₂ and H₂O₂ electroreduction processes were also studied. The pH dependencies of cobalt redox centers, and oxygen and hydrogen peroxide reductions were measured for the purpose of exploring the reaction mechanism. In neutral solutions, the oxygen reduction reaction was observed to be a two-electron process, producing H₂O₂ in the low potential polarization range. In the high potential polarization range, an overall four-electron reduction of O₂ to H₂O was found to be the dominating process. The kinetic parameters obtained from the RDE experiments indicate that in a neutral solution, the reduction rate at the step from H₂O₂ to H₂O is faster than that seen from O₂ to H₂O₂. Carbon particle-based air cathodes catalyzed by CoTMPP were fabricated for metal-air fuel cell application. The obtained non-noble catalyst content cathodes show considerably improved performance and stability. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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