The Effect of Anion Modification on the Conductive Polymer/Ag-Interdigitated Electrodes Micro-Supercapacitor

Due to their outstanding electrical conductivity, simplicity of synthesis, and exceptional flexibility, conductive polymers are the most attractive electrode materials for micro-supercapacitors (MSCs). However, when used as an electrode material alone, its poor capacitive performance and cycle-life hinder the wide engineering applications. Herein, a polypyrrole (PPy)/Ag-interdigitated electrodes MSCs is proposed, and the impact of aromatic sulfonic acid group anion modification on the electrochemical properties and flexibility of PPy/Ag MSCs is investigated. In the results, it is shown that different aromatic sulfonic-acid-based anionic dopants have different effects on the properties of PPy films. Among the prepared three PPy/Ag MSCs devices, PPy:anthraquinone-2-sulfonic acid/Ag MSCs have the highest areal capacitance (198.8 mF cm −2 ) at a current density of 0.5 mA cm −2 , surpassing PPy:2-naphthalenesulfonic acid/Ag MSCs (114.3 mF cm −2 ) and PPy:p-toluenesulfonic acid monohydrate/Ag MSCs (89.7 mF cm −2 ). Furthermore, at a power density of 0.25 mW cm −2 , the PPy:AQS/Ag MSCs exhibit a high energy density of 27.61 μWh cm −2 , which is above the most of the previously reported PPy-based MSCs. Therefore, in this research, the groundwork is provided for improving properties of flexible MSCs based on PPy.