Synthesis of a novel hybrid anode nanoarchitecture of Bi2O3/porous-RGO nanosheets for high-performance asymmetric supercapacitor

Novel bismuth oxide (Bi2O3) nanoparticles dispersed on porous reduced graphene oxide nanosheets is prepared using the facile hydrothermal reaction followed by a calcination process in the air atmosphere. At electrochemical study, the electrode materials of Bi2O3/porous-RGO display the capacitance retention to be 81.1% at a current density of 0.5 Ag-1 and α-MnO2-NRs exhibit about 80.7% at a scan rate of 10 mVs−1 for 3000 cycles in 6 M KOH electrolytes of three-electrode configuration. Moreover, the outstanding capacitance retention of anode and cathode materials mainly due to the porosity (porous-RGO), thermal stability with maximal weight loss rate temperature T(mwlr) reach of 623 °C, a smaller size of Bi2O3 (~7.5 ± 0.5 nm), and aspect ratio of α-MnO2 nanorods for 5.1 ± 0.9 nm. The assembled asymmetric supercapacitor (ASC) achieves the specific capacitance of 84 Fg-1 at a scan rate of 5 mVs−1 and capacitance retention of 91.4% at a current density of 1 Ag-1 by the Bi2O3/porous-RGO//α-MnO2-NRs in PVA/KOH gel electrolyte of two-electrode configuration. Notably, the ASC delivers an energy density of 86 Wh kg−1 (787 mF cm−2) at a power density of 9000 W kg−1. As a result, Bi2O3/porous-RGO and α-MnO2-NRs is considered as a promising candidate for future anode/cathode material in ASC energy storage device. [Display omitted] •Bismuth oxide nanoparticles were successfully dispersed on porous reduced graphene oxide nanosheets by catalytic carbon gasification method.•The capacitance retention of Bi2O3/porous-RGO and α-MnO2-NRs has been achieved up to 81.1% at 0.5 Ag-1 and 80.7% 10 mVs−1.•The ASC delivered an energy density of 86 Wh kg−1 (787 mF cm−2) at a power density of 9000 W kg−1