Fabrication of a flexible porous polypyrrole film with a 3D micro-nanostructure and its electrochemical properties

Flexible energy storage systems have become attractive alternatives for applications in wearable energy storage and sensor devices. This study reports a simple electro-polymerization method for the fabrication of PPy films coated on PPy nanotubes (PPy NTs), which are binding-free, self-standing, and could be used as a flexible electrode for supercapacitors. With optimized kinetics for ion transportation, the mass specific capacitance of the flexible porous PPy films can be elevated to 1.36 F cm(-2) at a charging/discharging rate of 2 mA cm(-2) (0.45 A g(-1)). The mass specific capacitance of the flexible porous PPy films reaches 6.5 times as large as that of compact PPy films at a scan rate of 20 mV s(-1). Furthermore, due to the large free space for volume change, the capacitance fading of the flexible porous PPy films is less than 3% after 10 000 cycles. This novel design provides an efficient method to synthesize high-performance, flexible and low-cost materials used in supercapacitors.

Automated summary

This study presents a simple electro-polymerization method to fabricate flexible PPy films coated on PPy nanotubes, which can be used as flexible electrodes for supercapacitors. The optimized kinetics for ion transportation result in a significantly increased mass specific capacitance of the flexible porous PPy films. The flexible porous PPy films also exhibit minimal capacitance fading after 10,000 cycles due to the large free space for volume change.