Metal-free porous nitrogen-doped carbon nanotubes for enhanced oxygen reduction and evolution reactions
Developing efficient metal-free bi-functional electrocatalysts is required to reduce costs and improve the slow oxygen reduction reaction (ORR) and oxygen evo- lution reaction (OER) kinetics in electrochemical systems. Porous N-doped carbon nanotubes (NCNTs) were fabri- cated by KOH activation and p...
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Published in | 中国科学通报:英文版 no. 11; pp. 889 - 896 |
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Main Author | |
Format | Journal Article |
Language | English |
Published |
2016
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Subjects | |
Online Access | Get full text |
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Summary: | Developing efficient metal-free bi-functional electrocatalysts is required to reduce costs and improve the slow oxygen reduction reaction (ORR) and oxygen evo- lution reaction (OER) kinetics in electrochemical systems. Porous N-doped carbon nanotubes (NCNTs) were fabri- cated by KOH activation and pyrolysis of polypyrrole nanotubes. The NCNTs possessed a large surface area of more than 1,000 m2 g-1. NCNT electrocatalysts, particu- larly those annealed at 900 ℃, exhibited excellent ORR electrocatalytic performance. Specifically, they yielded a more positive onset potential, higher current density, and long-term operation stability in alkaline media, when compared with a commercially available 20 wt% Pt/C catalyst. This resulted from the synergetic effect between the dominant pyridinic/graphitic-N species and the porous tube structures. The NCNT electrocatalyst also exhibited good performance for the OER. The metal-free porous nitrogen-doped carbon nanomaterials were prepared from low cost and environmentally friendly precursors. They are potential alternatives to Pt/C catalysts, for electrochemical energy conversion and storage. |
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Bibliography: | Developing efficient metal-free bi-functional electrocatalysts is required to reduce costs and improve the slow oxygen reduction reaction (ORR) and oxygen evo- lution reaction (OER) kinetics in electrochemical systems. Porous N-doped carbon nanotubes (NCNTs) were fabri- cated by KOH activation and pyrolysis of polypyrrole nanotubes. The NCNTs possessed a large surface area of more than 1,000 m2 g-1. NCNT electrocatalysts, particu- larly those annealed at 900 ℃, exhibited excellent ORR electrocatalytic performance. Specifically, they yielded a more positive onset potential, higher current density, and long-term operation stability in alkaline media, when compared with a commercially available 20 wt% Pt/C catalyst. This resulted from the synergetic effect between the dominant pyridinic/graphitic-N species and the porous tube structures. The NCNT electrocatalyst also exhibited good performance for the OER. The metal-free porous nitrogen-doped carbon nanomaterials were prepared from low cost and environmentally friendly precursors. They are potential alternatives to Pt/C catalysts, for electrochemical energy conversion and storage. N-doped porous carbon ; Polypyrrole ;Electrocatalyst ; Oxygen reduction reaction; Oxygenevolution reaction |
ISSN: | 1001-6538 1861-9541 |