An enhanced oxygen electrode catalyst by incorporating CoO/SnO2 nanoparticles in crumpled nitrogen-doped graphene in alkaline media
| Autor: | Xiuxiu Ma, Xingquan He |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Tafel equation
Graphene General Chemical Engineering Oxygen evolution Nanoparticle Nanotechnology 02 engineering and technology General Chemistry Overpotential 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Catalysis law.invention chemistry.chemical_compound chemistry Chemical engineering law 0210 nano-technology Bifunctional Clark electrode |
| Zdroj: | RSC Advances. 6:50017-50026 |
| ISSN: | 2046-2069 |
| Popis: | To address issues concerning energy consumption and the environment, it is of great importance to design a highly efficient, durable and inexpensive oxygen electrode for energy storage and conversion devices. In this work, CoO/SnO2 nanoparticles were successfully incorporated in nitrogen-doped graphene by a facile method. The composite was of porous structure, and exhibited efficient bifunctional activity and outstanding stability towards both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). For ORR, the catalyst favored a direct four-electron-transfer pathway, and produced kinetic current density values close to those of Pt/C. In addition, for OER, it achieved a lower overpotential at a current density of 10 mA cm−2 and a smaller Tafel slope than RuO2. What is more, the value of the potential difference ΔE(OER–ORR), a measure of the overall bifunctionality of the catalyst, was 0.72 V, comparable with the values for state-of-the-art nonprecious bifunctional catalysts. The remarkable bifunctional activity of the catalyst was mainly attributed to the synergistic effects between metal oxides and nitrogen-doped graphene. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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