Pt nanoflower-poly(aniline) electrode material with the synchronized concept of energy storage in supercapacitor

Abstract

Electrochemically deposited porous film of poly(aniline) (PANI) on stainless steel (SS) current collector is employed as the support for electrodeposition of platinum (Pt). PANI facilitates the formation of Pt nanoflowers with an enhanced electrochemically active surface area compared with sub-micron size Pt particles deposited on the bare SS electrode. Hence, anew conceptPt nanoflower-PANI electrode materials withsynchronization between redox mode in PANI and double-layer mode of charge storage in Pt nanofloweris discussed. Remarkably, Pt is distributed like a nano-flower on the surface of PANI and prevents PANI from stripping during the charge-discharge process, thereby minimizing the issue of stripping in conducting polymer-based electrodes. Owing to the highly porous surface morphology of Pt nanoflowers as observed in SEM, the Pt-PANI/SS electrode shows excellent electrochemical performance than PANI/SS electrode towards supercapacitor application. The electrode materials are characterized using X-ray and X-ray photon spectroscopy (XPS), which shows dual amorphous and crystalline properties. Dielectric studies of Pt-PANI/SS electrodes were carried out to understand electrode/electrolyte interface behavior. In the fabricated supercapacitor, the cyclic voltammetry studies showed quasi-rectangular shape characteristics at slower scan rates with a specific capacitance of 926 Fg−1. Charge-discharge studies showed good cyclic stability and coulombic efficiency.