Crafting advanced supercapacitor electrodes with calcium manganese oxide in synergy with rGO and MWCNTs

Abstract

Despite significant progress in developing metal oxide composite electrodes, methods to improve conductivity and integrate them with carbon nanocomposites remain scarce. Herein, we have synthesized carbon variants – metal oxide composite electrodes with reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs). This study outlines the process of synthesizing CaMn3O6 microbeads (∼0.4 μm), which are dispersed within reduced graphene oxide (rGO) sheets and carbon nanotubes (CNTs). The synthesis involves a hydrothermal reaction followed by a calcination process. The synthesized samples are fabricated as a pouch type asymmetric supercapacitor device. The electrodes labelled as CMO–G and CMO–M were tested in three electrode system wherein CMO–M delivered a capacitance of 483 F/g and CMO-G delivered a capacitance of 356 F/g. Low resistance, excellent cycling stability makes CMO–M a suitable electrode for practical applications. The device CMO–M||AC delivered capacitance of 140 F/g and showed a capacity retention up to 84 % even after 20,000 cycles. CMO–M||AC device delivered energy density of 43.81 Wh kg−1 at 750 W kg−1 power density. Our results distinctly demonstrate the significant potential achieved through the synergistic effect in CaMn3O6 and carbon variants. This understanding could prove valuable in the creation of advanced energy storage solutions.