Decoration of CeO2 nanoparticles on hierarchically porous MnO2 nanorods and enhancement of supercapacitor performance by redox additive electrolyte

Pure CeO2 nanoparticles (NPs) and MnO2 nanorods (NRs) have been prepared by the hydrothermal technique. The CeO2 NPs were uniformly coated over the MnO2 NRs through a facile ultrasonic technique. The uniform distribution of CeO2 NPs over MnO2 NRs has been analysed by scanning electron microscopy. Crystalline phases of pure CeO2, MnO2, and the formation of CeO2 NPs decorated MnO2 NRs have been studied by XRD analysis. The absence of inorganic residuals over the prepared nanomaterials was confirmed by FT-IR analysis. The surface chemical composition and the formation of CeO2 NPs decorated MnO2 NRs have been studied by XPS analysis. The electrochemical performances of the prepared sample have been studied in 3 M aqueous KOH electrolyte and 0.2 M K4[Fe(CN)6] added 3 M KOH electrolyte. CeO2 nanoparticles decorated MnO2 nanorods exhibited the superior capacitance of 1058.2 Fg−1. [Display omitted] •CeO2 NPs decorated MnO2 NRs were synthesized through a novel ultrasonication method.•Electrochemical performances were studied using 3 M KOH and 3 M KOH +0.2 M K4[Fe(CN)6] electrolytes.•Superior specific capacitance of 1058.2 Fg−1 was achieved in 3 M KOH +0.2 M K4[Fe(CN)6] electrolyte.•Retention of 91.6% capacitance was achieved after 5000 GCD cycles.