Flexible supercapacitors based on a ternary composite of polyaniline/polypyrrole/graphite on gold coated sandpaper

Developing low-cost and efficient flexible supercapacitors is an important step towards the production of new energy storage systems for efficient wearable electronic devices. In this work, we report a simple and cost-effective approach to produce flexible electrodes for supercapacitors. The system consists of a complex ternary structure of hierarchical polyaniline (PAn) assembled on a polypyrrole (PPy) layer deposited on graphite pencil traces (Grt) in sandpaper. The proposed ternary composite PAn-PPy-Grt-Sp assembled in a device offered a maximal areal capacitance of 55.35 mF cm-2 at 0.3 mA cm−2, a higher value when compared to its counterparts of PAn-Grt-Sp (31.8 mF cm−2) and PPy-Grt-Sp (19.75 mF cm−2). The ternary composite also exhibited a higher energy (4.92 μWh cm−2) and power density (87.09 μW cm−2) at a current density of 0.3 mA cm−2 producing a more equilibrated supercapacitor device. The response to mechanical efforts returned negligible variation in electrochemical properties while cyclability remains as 80% of initial value after 3000 cycles.