Polypyrrole and cotton fabric-based flexible micro-supercapacitors

With the development of wearable electronic devices, there has been extensive research interest in portable energy supply systems. In this study, traditional cotton fabrics are finished with a water repellent coating and a single-sided polyurethane (PU) coating to impart hydrophobicity. The hydrophobic lightweight cotton fabric can float on the surface of the pyrrole polymerization system solution. With increasing polymerization time, the pyrrole continues to polymerize and deposit on the side in contact with the fabric, resulting in a one-sided conductive fabric. The highest doping level was obtained for the polypyrrole (PPy) coating for polymerization time of 12 h. For PPy coating thickness of 18 mu m, the square resistance was as low as 220 omega/sq. The PPy-12 fabric electrode showed excellent electrochemical performance and cycling stability. An interdigitated pattern was etched on the surface of the one-sided conductive fabric (PPy-12) using a N, N-dimethylformamide solution. Fabric micro-supercapacitors were obtained by assembling with a H2SO4/PVA gel electrolyte. The fabric micro-supercapacitor exhibited good flexibility and electrochemical energy storage properties. For current density of 0.08 mA/cm(2) and power density of 19.1 mu W/cm(2), the energy density of the device was 0.09 mu Wh/cm(2). After 3000 cycles, the micro-supercapacitor retained approximately 85% of the capacitance. Thus, fabric-based flexible micro-supercapacitors have excellent application potential in the field of energy storage.