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Two-dimensional ?-MnO? nanowire network with enhanced electrochemical capacitance.

ABSTRACT: Conventional crystalline ?-MnO2 usually exhibits poor electrochemical activities due to the narrow tunnels in its rutile-type structure. In this study, we synthesized a novel 2D ?-MnO2 network with long-range order assembled by ?-MnO2 nanowires and demonstrated that the novel 2D ?-MnO2 network exhibits enhanced electrochemical performances. The 2D network is interwoven by crossed uniform ?-MnO2 nanowires and the angle between the adjacent nanowires is about 60°. Such a novel structure makes efficient contact of ?-MnO2 with electrolyte during the electrochemical process, decreases the polarization of the electrode and thus increases the discharge capacity and high-rate capability. The specific capacitance of the obtained 2D ?-MnO2 network is 453.0 F/g at a current density of 0.5 A/g.

SUBMITTER: Wei C

PROVIDER: S-EPMC3709167 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Two-dimensional β-MnO₂ nanowire network with enhanced electrochemical capacitance.

Wei Chengzhen C Pang Huan H Zhang Bo B Lu Qingyi Q Liang Shuang S Gao Feng F

Scientific reports 20130101

Conventional crystalline β-MnO2 usually exhibits poor electrochemical activities due to the narrow tunnels in its rutile-type structure. In this study, we synthesized a novel 2D β-MnO2 network with long-range order assembled by β-MnO2 nanowires and demonstrated that the novel 2D β-MnO2 network exhibits enhanced electrochemical performances. The 2D network is interwoven by crossed uniform β-MnO2 nanowires and the angle between the adjacent nanowires is about 60°. Such a novel structure makes effi ...[more]

PMID: 23846740

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