Sprayed bismuth oxide interconnected nanoplate supercapacitor electrode materials

Abstract

In the present article we report synthesis and electrochemical supercapacitor applications of sprayed bismuth oxide (Bi2O3) interconnected upright standing nano-plate-based electrode material via a simple spray pyrolysis aqueous route onto a flexible 3D Ni-foam at 623 ± 2 K. The Bi2O3 Ni-foam was initially characterized for its structure, morphology and phase-purity analyses and then envisaged as electrode materials in supercapacitor applications. Polycrystalline, cubic crystal structure of Bi2O3 nanoplate films were hydrophobic in character. The cyclic voltammetry curves of Bi2O3 electrode, scanned at scan rates from 5 to 1000 mV/s in 1 M Na2SO4 electrolyte in the potential window of −0.8 – 1.9 V vs. Ag/AgCl confirm a mixed-type capacitive behavior. Using charge-discharge study, the calculated maximum values of specific energy, specific power and columbic efficiency were 702.97 Wh/kg, 334.7 kW/kg and 99.9%, respectively. Electrochemical impedance measurement scanned in the frequency range of 1 mHz–1 MHz confirms ∼6 Ω solution resistance and ∼13 Ω charge transfer resistance. An excellent electrochemical stability of 92% at 100 mV/s scan rate even after 5000 redox cycles demonstrates an industrial potential of Bi2O3 electrode materials.