Flexible, symmetric supercapacitor using self-stabilized dispersion-polymerised polyaniline/V2O5 hybrid electrodes

Supercapacitors are attracting significant interest owing to their potential in high power applications. The lack of energy density is one of the main drawbacks observed in supercapacitors. A hybrid electrode made from polyaniline (PANi) synthesized by an organic mediated self-stabilized polymerisation method and V2O5 nanoparticles, is introduced in this work and the electrochemical performance is evaluated both in three- and two- electrode symmetric configurations. The incorporation of this high molecular weight PANi with nanostructured V2O5 effectively addresses the shortcomings of these individual materials and exhibits a synergistic effect as evident from the performance of the hybrid electrode. From the different compositions of PANi and V2O5 studied, the PV3 electrode (PANI: V2O5 = 3:1) exhibits the highest gravimetric capacitance of 498 F g−1 at a current density of 1 A g−1. This champion electrode retains 84% of its initial capacitance even at a high current density of 20 A g−1. The symmetric supercapacitor fabricated using this binder-free electrode exhibits a capacitance of 260 F g−1 at a current density of 1 A g−1 and displays a high energy density of 36 Wh kg−1 at a power density of 1 kW kg−1. The symmetric device is also found to be highly flexible and shows a cycling stability of 94.4% even after 10,000 continuous charge–discharge cycles at a current density of 10 A g−1. These results point towards the potential of this hybrid electrode for next generation wearable electronic applications.