Spherical bismuth iron oxide nanostructures as battery-type negative electrode for supercapacitor applications

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Switzerland), 2025-02, Vol.978, Article 118869
• Main Authors: Johnson William, J., Manohara Babu, I., Muralidharan, G.
• Format: Article
• Language: English
• Subjects: Battery-type; Bismuth iron oxide; Microwave; Quasi-conversion reaction; Supercapacitor
• ISSN: 1572-6657
• DOI: 10.1016/j.jelechem.2024.118869

•BiFeO3/Bi2Fe4O9 nanocomposites were designed using microwave technique.•A maximum of 445 C/g was obtained along with 82 % retention after 2000 cycles.•The fabricated cell could yield energy density of 65 Wh kg−1 at 214 W kg−1.•The designed cell could light up the array of 60 Red LEDs. Extensive research is needed in the field of energy storage devices in the development of electrochemically well performing negative electrodes. Herein, bismuth ferrite nanostructures were prepared through a green chemistry route using microwave irradiation technique. The X-ray diffraction analysis confirms that the prepared bismuth iron oxide nanostructures are comprised of perovskite BiFeO3 and mullite Bi2Fe4O9. The chemical environment around Bi, Fe and O element is examined using X-ray photoelectron spectroscopy. The structural characteristics of the bismuth iron oxide nanostructures were diagnosed using transmission electron microscopy, confirming the formation of nano-sized spherical particles. Half-cell mode was employed to study the charge storage characteristics of the prepared materials. The cyclic voltammetry and galvanostatic charge–discharge test on the electrodes of the prepared materials implies that the electrochemical performance is controlled by the quasi-conversion reaction mechanism and it could yield a maximum specific capacity of 445 C/g at a constant current density of 2 mA cm−2. A battery-type asymmetric supercapacitor cell was devised using ternary Ni-Ce-Ag-O metal oxide nanocomposites as the counter electrode to the bismuth iron oxide nanostructures. The charge storage performance of the fabricated was assessed within the operating voltage of 1.5 V and it could yield a maximum energy density of 65 W h kg−1 at a power density of 214 W kg−1. Moreover, the charged cell could power up an array of 60 Red LEDs, signifying the potentiality of the prepared electrodes. The findings of the present study strongly support that the bismuth iron oxide nanostructures can be a suitable material for the fabrication of a battery-type negative electrode for asymmetric supercapacitor applications.