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Ultranarrow Graphene Nanoribbons toward Oxygen Reduction and Evolution Reactions.

ABSTRACT: Identification of catalytic sites for oxygen reduction and evolution reactions (ORR/OER) is critical to rationally develop highly efficient bifunctional carbon-based metal-free electrocatalyst. Here, a unique defect-rich N-doped ultranarrow graphene nanoribbon with a high aspect ratio that exhibits excellent ORR/OER bifunctional activities and impressive long-term cycling stability in Zn-air batteries is successfully fabricated. Density functional theory calculations indicates that the topological defects (e.g., pentagons and heptagons) cooperated with pyridinic-N dopants on the edges are more favorable to electrocatalytic activity toward ORR and OER. This work provides a new design principle for carbon-based electrocatalytic nanomaterials.

SUBMITTER: Zhang J

PROVIDER: S-EPMC6299708 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Ultranarrow Graphene Nanoribbons toward Oxygen Reduction and Evolution Reactions.

Zhang Jian J Sun Yuanmiao Y Zhu Jiawei J Gao Zhonghui Z Li Shuzhou S Mu Shichun S Huang Yunhui Y

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20181106 12

Identification of catalytic sites for oxygen reduction and evolution reactions (ORR/OER) is critical to rationally develop highly efficient bifunctional carbon-based metal-free electrocatalyst. Here, a unique defect-rich N-doped ultranarrow graphene nanoribbon with a high aspect ratio that exhibits excellent ORR/OER bifunctional activities and impressive long-term cycling stability in Zn-air batteries is successfully fabricated. Density functional theory calculations indicates that the topologic ...[more]

PMID: 30581716

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