Heterogeneous interface induced formation of balsam pear-like PPy for high performance supercapacitors

In this work, we have put forward a novel heterogeneous interface induced formation strategy to prepare balsam pear-like polypyrrole (PPy) film by using binary electrodeposition. The as-prepared PPy film exhibited a balsam pear-like structure with plenty of vertically aligned serrations and offered a longer conjugation length of PPy chains. Beneficial from the reasonable structure, the serrated PPy (SE-PPy) provided abundant electro-active contact area with the electrolyte, thus leading to the ultrafast-spreading of electrolyte ions and high utilization efficiency of active electrode. Based on this, the SE-PPy electrode showed outstanding electrochemical performance with a large specific capacitance of 773.6 F/g at 1 A/g in 1 M KOH electrolyte, and still retains similar to 77.6% of its initial capacitance at a high current density of 20 A/g, which is superior to the reported PPy and most of PPy-related electrodes. (C) 2019 Elsevier B.V. All rights reserved.