Facile synthesis of rod-like Bi2O3 nanoparticles as an electrode material for pseudocapacitors

Abstract The present paper reports the synthetic route of Bi 2 O 3 with rod-like architectures and its applications in supercapacitors. The rod-like Bi 2 O 3 was prepared via a sol–gel method using Bi(NO 3 ) 3 ·5H 2 O as a precursor. The structures and morphology of the synthesized samples were characterized by X-ray diffractions (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and nitrogen gas sorption, while their electrochemical properties were carried out using cyclic voltammetry (CV), galvanostatic charge–discharge test and electrochemical impedance spectroscopy (EIS). XRD patterns revealed that the pure β-Bi 2 O 3 phase was obtained and the electrochemical measurement showed that the material exhibited a specific capacitance of 528 F g −1 at the scan rate of 5 mV s −1 with superior rate capability. Furthermore, the electrode material shows good cycle stability in the potential range of −1.1 to 0.2 V (vs. saturated calomel electrode (SCE)) after 1000 cycles. The results indicate that the as-prepared Bi 2 O 3 is a promising electrode material for pseudocapacitors application.