Abstract A core/shell polyaniline (PANI)/MnO2 composite (denoted as “PANI@MnO2”) was prepared and evaluated as electrode material for supercapacitor applications. In the composite, α-MnO2 showed chrysanthemum-like and spherical structure, which were coated in situ with PANI. In this process, α-MnO2 serves as a scaffold and also acts as an oxidant to induce aniline polymerization. Scanning electron microscopy and transmission electron microscopy images clearly showed the core/shell structure of the PANI@MnO2 composite, which was further characterized by X-ray powder diffraction, Fourier transformation infrared spectroscopy and Raman spectroscopy. In addition, the thermo-gravimetric analysis illustrates that the composite has a good thermal stability and the mass ratio of PANI and MnO2 is 0.11. Electrochemical properties of the composite and its components were evaluated using cyclic voltammetry, electrochemical impedance spectra and chronopotentiometry. The specific capacitance of the high-mass loading PANI@MnO2 electrode is 75 Fg−1, 1.1 times higher than that of MnO2 electrode (67 Fg−1), at a current density of 0.1Ag−1. Moreover, the composite electrode retains 90% of the initial capacitance after 3000 cycles, while this is only 75% for α-MnO2. The improved electrochemical performance may be attributed to the synergistic effect between PANI and α-MnO2.

中文翻译：

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通过聚苯胺原位涂层增强α-MnO2的伪电容性能

摘要 制备了核/壳聚苯胺 (PANI)/MnO2 复合材料（表示为“PANI@MnO2”），并将其用作超级电容器应用的电极材料。在复合材料中，α-MnO2 呈菊花状和球形结构，并在原位用 PANI 包覆。在此过程中，α-MnO2 作为支架，也作为氧化剂诱导苯胺聚合。扫描电子显微镜和透射电子显微镜图像清楚地显示了PANI@MnO2复合材料的核/壳结构，并通过X射线粉末衍射、傅里叶变换红外光谱和拉曼光谱进一步表征。此外，热重分析表明该复合材料具有良好的热稳定性，PANI与MnO2的质量比为0.11。使用循环伏安法、电化学阻抗谱和计时电位法评估复合材料及其组分的电化学性能。在0.1Ag-1的电流密度下，高质量负载PANI@MnO2电极的比电容为75 Fg-1，是MnO2电极（67 Fg-1）的1.1倍。此外，复合电极在 3000 次循环后仍保留 90% 的初始电容，而 α-MnO2 仅为 75%。改进的电化学性能可能归因于 PANI 和 α-MnO2 之间的协同作用。复合电极在 3000 次循环后仍保留 90% 的初始电容，而 α-MnO2 仅为 75%。改进的电化学性能可能归因于 PANI 和 α-MnO2 之间的协同作用。复合电极在 3000 次循环后仍保留 90% 的初始电容，而 α-MnO2 仅为 75%。改进的电化学性能可能归因于 PANI 和 α-MnO2 之间的协同作用。