Abstract Fe-doped δ-MnO2 nanoneedles have been successfully synthesized via a hydrothermal method as electrode materials. The morphologies of as-synthesized samples were characterized by SEM and the role of Fe3+ as a structure directing agent on the formation of MnO2 nanoneedles was investigated. The electrode exhibits maximum specific capacitance of 627.3 F g−1 at a current density of 1 A g−1, far exceeding the capacity of MnO2 monomers. Furthermore, the capacitance retention was measured to be 94.2% after 3000 cycles, showing remarkable cycling stability. The activation of Fe3+ in δ-MnO2 nanoneedles attributes to the enhancement of electrode conductivity and electrochemical performance. In principle, the results indicate the potential application of our samples in supercapacitor electrodes.

中文翻译：

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Fe掺杂的δ-MnO 2 纳米针作为先进的超级电容器电极

摘要 Fe掺杂的δ-MnO2纳米针作为电极材料已通过水热法成功合成。合成样品的形态通过扫描电镜表征，并研究了 Fe3+ 作为结构导向剂对 MnO2 纳米针形成的作用。该电极在 1 A g-1 的电流密度下表现出 627.3 F g-1 的最大比电容，远远超过 MnO2 单体的容量。此外，在 3000 次循环后测得的电容保持率为 94.2%，显示出显着的循环稳定性。Fe3+在δ-MnO2纳米针中的活化归因于电极电导率和电化学性能的增强。原则上，结果表明我们的样品在超级电容器电极中的潜在应用。