Abstract A 3D porous carbon-manganese oxide (3D-C@MnO) nanocomposite is successfully synthesized via a thermal plasma deposition method. The chemical bonds and compositions, phase structures, surface morphologies, etc. of as-obtained 3D-C@MnO nanocomposite were characterized by the various equipment, such as X-ray diffractometer, X-ray photoelectron spectroscopy, and electron microscopes. The electrochemical performances of the 3D-C@MnO nanocomposite electrode showed a specific capacitance of 780 F g−1 at a current density of 2 A g−1 and a capacitance retention rate of 99% after 5000 charge-discharge cycles at a high current density of 10 A g−1. These excellent capacitive performances may be attributed to the encapsulation of MnO nanoparticles by porous carbon sheets in the 3D-C@ MnO nanocomposite structure. It is believed that the carbon-encapsulated MnO nanoparticles can be protected from a volume deformation during the charge adsorption/desorption cycle and can be electrically improved by the encapsulated carbon sheets, resulting in better overall capacitive performance. In addition, this study also demonstrates the practical applicability by assembling a supercapacitor using the as-obtained 3D-C@MnO nanocomposite to glow a light emitting diode.

中文翻译：

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3D多孔碳锰氧化物（3D-C@MnO）纳米复合材料的合成及其超级电容器行为研究

摘要 通过热等离子体沉积法成功合成了 3D 多孔碳锰氧化物 (3D-C@MnO) 纳米复合材料。通过X射线衍射仪、X射线光电子能谱和电子显微镜等多种设备对所获得的3D-C@MnO纳米复合材料的化学键和组成、相结构、表面形貌等进行了表征。3D-C@MnO纳米复合电极的电化学性能在2 A g-1的电流密度下比电容为780 F g-1，在大电流下5000次充放电循环后电容保持率为99%密度为 10 A g−1。这些优异的电容性能可能归因于 3D-C@MnO 纳米复合结构中的多孔碳片包裹了 MnO 纳米颗粒。据信，碳包封的 MnO 纳米颗粒可以在电荷吸附/解吸循环期间免受体积变形的影响，并且可以通过包封的碳片进行电学改进，从而获得更好的整体电容性能。此外，本研究还通过使用所获得的 3D-C@MnO 纳米复合材料组装超级电容器来发光发光二极管来证明其​​实际适用性。