不同磺酸掺杂聚苯胺的制备及在超级电容器中的应用

以MnO₂为氧化剂,采用乳液聚合法,用三种不同的磺酸型表面活性剂制备掺杂聚苯胺(PANI)。通过扫描电子显微镜(SEM)、傅里叶变换红外(FTIR)光谱以及X射线衍射(XRD)等手段对其结构及形貌进行表征;用所得的掺杂聚苯胺制作电极,组装成对称扣式超级电容器,用循环伏安法(CV)、电化学阻抗(EIS)和恒电流充放电技术进行电化学性能研究。结果表明,磺酸表面活性剂的引入有利于PANI纳米纤维的形成和分散,掺杂Nafion的PANI纤维直径在30-40 nm之间,纤维交织成多孔的疏松结构;当放电电流为0.1 A·g^-1时,以PANI-Nafion、PANI-SDS(十二烷基磺酸钠)、PANI-SDBS(十二烷基苯磺酸钠)为电极材料的超级电容器比容量分别为385.3、359.7、401.6 F·g^-1,均高于未掺杂PANI的比容量(235.8 F·g^-1);其中, PANINafion的循环稳定性最好, 1000次循环后其比容量保持率高达70.7%。

Preparation and Application of Polyaniline Doped with Different Sulfonic Acids for Supercapacitor

Polyaniline (PANI) nanomaterials doped with three different sulfonic acid surfactants (perfluorinated sulfonic acid ion exchange resin (Nafion), sodium dodecyl sulfate (SDS), and sodium dodecyl benzene sulfonate (SDBS)) were prepared using an emulsion polymerization method with manganese dioxide (MnO₂) as the oxidant. The structure and morphology of the products were studied by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). Symmetric redox supercapacitor was assembled with doped PANI as the active electrode material. The electrochemical performances of the materials were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge tests. These results suggest that the introduction of surfactant is beneficial for the formation of a fiber structure and increases the dispersion of PANI. A PANI-Nafion network with distributed porosity and average diameters of 30-40 nm is obtained. The specific capacitances of PANI-Nafion, PANI-SDS, and PANI-SDBS electrodes at 0.1 A·g^-1 are 385.3, 359.7, and 401.6 F·g^-1, respectively. Among these electrodes PANI-Nafion delivers the best cycle performance, maintaining 70.7% of its initial capacitance after 1000 cycles.