Nitrogen-doped hollow carbon polyhedron derived from salt-encapsulated ZIF-8 for efficient oxygen reduction reaction
Autor: | Liwei Shen, Jin Yan, Kai Zeng, Ruizhi Yang, Xiangjun Zheng, Mark H. Rümmeli, Zhihui Sun, Chaohui Wei, Jiawen Sun |
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Rok vydání: | 2021 |
Předmět: |
Battery (electricity)
Materials science Kinetics chemistry.chemical_element 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Nitrogen Cathode 0104 chemical sciences Catalysis law.invention Chemical engineering chemistry law General Materials Science 0210 nano-technology Porosity Carbon Power density |
Zdroj: | Carbon. 171:320-328 |
ISSN: | 0008-6223 |
Popis: | The sluggish kinetics of oxygen reduction reaction (ORR) seriously restrains the practical implementation of fuel cells and metal-air batteries (MABs). While, Pt-based catalysts are well proven to be effective for the ORR process, they are rather expensive. Therefore, it is critical to developing low-cost and advanced catalysts with a rationally designed structure and abundant reactive sites as alternatives for Pt-based catalysts. Herein, nitrogen-doped hollow carbon polyhedrons (NHCP) have been fabricated by directly pyrolyzing ZIF-8, templated by NaCl. Benefiting from their hollow porous structure, large surface area, high graphitization degree and desired nitrogen bonding type, the as-synthesized NHCP exhibits exceptional ORR electrocatalytic activity with a half-wave potential (E1/2) of 0.86 V, high selectivity and outstanding long-term stability, exceeding most reported nitrogen-doped metal-free carbon electrocatalysts. Furthermore, the assembled Zn-air battery with NHCP cathode delivers a peak power density of 272 mW cm−2, a specific capacity of 740 mAh g−1 and an operation period of 160 h. This contribution provides a new avenue for designing high-performance electrocatalysts for ORR. |
Databáze: | OpenAIRE |
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