二氧化锰含量对活性炭电极电化学性能的影响

本文采用液相法、热分解MnCO₃法以及电解沉积法制备不同二氧化锰粉末，并将其与活性炭复合，应用于水系超级电容器. 使用X射线衍射（XRD）、扫描电子显微镜（SEM）技术对材料形貌进行表征. 使用循环伏安法以及恒流充放电法对其电化学性能进行测试. 实验数据表明，α-MnO₂（质量分数70%）掺杂活性炭电极的最大比容量为151 F•g^-1，β-MnO₂（质量分数60%）掺杂活性炭电极的最大比容量为172F•g^-1，γ-MnO₂（质量分数50%）掺杂活性炭电极的最大比容量为141F•g^-1，但二氧化锰粉末对电极内阻的影响呈无规律性.

Effect of MnO2 Content on Electrochemical Capacitance Behavior of Active Carbon Electrode

In this work, the manganese dioxide (MnO₂) materials were prepared by solution approach at low temperature, thermal decomposition and electrochemical deposition. The actived carbon (AC) and MnO₂ composite electrodes were used for aqueous supercapacitors. The morphologies and structures of the prepared materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the electrochemical behaviors were tested by cyclic voltammetry (CV) and galanostatic charge-discharge tests. Electrochemical test data show that the maximum specific capacitances of 151, 172 and 141 F•g^-1 were obtained with the contents of MnO₂ being 70, 60 and 70% in the composites, respectively. However, the influence of MnO₂powder on the electrode impedance was not straightforward.