Abstract Mn3O4 nanoparticles were anchored on the surface of oxidised graphite paper via template-free hydrothermal method. Synthesized samples were characterized using different techniques such as X-ray diffraction (XRD), Raman spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), High Resolution Transmission Electron Microscopy (HRTEM) and X-ray Photoelectron Spectroscopy (XPS). Electrochemical capacitor behaviour was evaluated using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The binder free material was found to exhibit a specific capacitance of 471 F g−1 at a current density of 1 mA cm−2 in 1 M Na2SO4. Conductive additive free, Mn3O4 anchored electrode was used as positive electrode in the asymmetric cell fabrication; the asymmetric cell was tested at a potential window of 1.6 V and its performance characteristics were evaluated. The asymmetric cell delivered a maximum specific energy of 47 Wh kg−1 at a power density of 202.5 W kg−1 which evidenced the superior performance of the synthesized electrode material. Here in the present work, the surface oxidised graphite paper was used as an excellent current collector and active sites for anchoring Mn3O4 due to its desirable properties.

中文翻译：

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Mn 3 O 4 纳米颗粒生长在表面活性石墨纸上，用于水不对称超级电容器

摘要 采用无模板水热法将Mn3O4纳米颗粒锚定在氧化石墨纸表面。合成样品使用不同的技术进行表征，例如 X 射线衍射 (XRD)、拉曼光谱、场发射扫描电子显微镜 (FE-SEM)、高分辨率透射电子显微镜 (HRTEM) 和 X 射线光电子能谱 (XPS)。使用循环伏安法 (CV)、恒电流充放电 (GCD) 和电化学阻抗谱 (EIS) 评估电化学电容器行为。发现无粘合剂材料在 1 M Na2SO4 中在 1 mA cm-2 的电流密度下表现出 471 F g-1 的比电容。不含导电添加剂的 Mn3O4 锚定电极用作非对称电池制造中的正极；不对称电池在 1.6 V 的电位窗口下进行了测试，并对其性能特性进行了评估。不对称电池在 202.5 W kg-1 的功率密度下提供了 47 Wh kg-1 的最大比能量，这证明了合成电极材料的优越性能。在目前的工作中，由于其理想的特性，表面氧化石墨纸被用作优异的集电器和用于锚定 Mn3O4 的活性位点。