Abstract Herein, the flower-like manganese oxide was synthesized by a hydrothermal method, and then modified by plasma H2 for different time to create oxygen vacancies. The longer the treating time, the higher the concentration of oxygen vacancies. Meanwhile, the crystal structure and morphology of MnO2 material remain the same as the raw material after plasma H2 treatment. The sample modified by plasma H2 for 10 min (MnOx-10) exhibited a high specific capacitance of 296.9 F g−1 at 0.5 A g−1 and a superior cycling stability with a capacity retention of 90.0 % after 5000 cycles. Moreover, the asymmetric supercapacitor (ASC) using the as-prepared MnOx-10 as cathode and Kochen Black (KB) as anode was fabricated and showed an outstanding cyclic stability with a capacity retention of 90.0 % after 5000 cycles and a high energy density of 61 Wh kg−1 at a corresponding power density of 750 W kg−1. This study provided a comprehensive understanding of plasma H2 as an effective technique for introducing oxygen vacancies and further broaden the application of manganese oxide as a kind of high capacity and low cost electrode materials.

中文翻译：

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基于等离子改性的富氧空位氧化锰用于高性能超级电容器

摘要 本文采用水热法合成了花状氧化锰，然后用等离子H2改性不同时间产生氧空位。处理时间越长，氧空位浓度越高。同时，MnO2 材料的晶体结构和形貌在等离子 H2 处理后保持与原材料相同。用等离子体 H2 改性 10 分钟（MnOx-10）的样品在 0.5 A g-1 下表现出 296.9 F g-1 的高比电容和优异的循环稳定性，5000 次循环后容量保持率为 90.0%。此外，使用所制备的 MnOx-10 作为阴极和 Kochen Black (KB) 作为阳极制造了不对称超级电容器 (ASC)，并显示出优异的循环稳定性和 90 的容量保持率。5000 次循环后为 0 %，能量密度为 61 Wh kg-1，相应的功率密度为 750 W kg-1。该研究提供了对等离子体 H2 作为引入氧空位的有效技术的全面理解，并进一步拓宽了锰氧化物作为一种高容量和低成本电极材料的应用。