Synthesis of Pd-Fe2O3 nanoflakes nanocomposite for superior energy storage device

Abstract

Background: The synthesized nanocomposites have enhanced stability due to the composite effect, high surface area, pore volume, and low charge transfer resistance of the nanocomposite. Moreover, the prepared nanocomposites reveal excellent specific capacitance, fast charge-discharge, and long-term durability. Method: The Pd-Fe2O3 nanoflakes nanocomposite has been prepared by the simple redox reaction under hydrothermal conditions. Significant findings: The as-synthesized Pd-Fe2O3 nanoflakes nanocomposite shows excellent capacitance of 531 F g-1 at a current density of 1 A g- 1 under acidic electrolyte whereas, the commercial Fe2O3 shows only 215 F g-1. The charge-storage mechanism of as-synthesized nanocomposite shows the major capacitive contribution to store the total charge. Further, a solid-state asymmetric supercapacitor device fabricated and exhibits excellent capacitance of 137 F g- 1 at 1 A g-1 current density using PVA-H2SO4 gel electrolyte along with a maximum energy density of 61.65 Wh kg- 1 and power density of 3.5 kW kg- 1. Interestingly, the as-synthesized Pd-Fe2O3 nanoflakes nanocomposite shows outstanding stability up to 8000 continuous charge-discharge cycles using the acidic electrolyte. The retention-specific capacitance of the nanocomposite is found to be 87% after cycles stability.