Promoting Oriented Growth of a Polyaniline Array on Carbon Cloth through in Situ Chemical Polymerization under a High Voltage Electric Field for a Flexible Supercapacitor with High Areal Capacity and Stability

An effective approach for boosting oriented growth of polyaniline (PANI) arrays on carbon cloth (CC) is presented through spraying and in situ chemical polymerization under a high voltage electric field for fabricating a high performance flexible supercapacitor. The morphology of PANI can be well controlled from nanocone and nanowire to nanofiber arrays by simply increasing the aniline concentration, and more importantly, significant improvement on the electrochemical properties can be efficiently achieved through constructing the desired architectures to greatly utilize synergistic interactions. The maximum gravimetric capacitance is 1269.5 F g–1 for a nanowire array, while the maximum areal capacitance is 1459.2 mF cm–2 for 1.44 mg cm–2 PANI nanofiber loading. Both the retentions in the capacitances are more than 76%, indicating that fast energy storage kinetics can be remained. Furthermore, a maximum energy density of 74.4 μWh cm–2 is delivered for the assembled flexible supercapacitor at a power density of 500.0 μW cm–2, meanwhile the rate retention of 81% and capacitance retention of up to 92% after 5000 cycles are obtained. This approach provides a great opportunity for developing advanced lightweight flexible energy storage devices and, especially, is suitable to large-scale production of PANI arrays on a conductive substrate through simply introducing a multi-needle electrospinning system.