Phase transformation in wet chemically synthesized Y2NiFeO6, and its magnetic and energy storage properties

Abstract

In this work we report, the structural, magnetic, and energy storage properties of double perovskite oxide Y2NiFeO6 synthesized via wet chemical sol–gel process. The amorphous phase structure obtained at the synthesis temperature of 650 °C, turned to mixed cubic-hexagonal phase of Y2NiFeO6 at 850 °C, and subsequently to thermally stable mixed cubic-orthorhombic phase at and above the temperature of 950 °C. The X-ray photoelectron spectra of thermally stable phase of Y2NiFeO6 exhibited the presence of yttrium in Y3+ state, nickel in Ni2+/Ni3+ state and iron in Fe3+ state. The Y2NiFeO6 exhibited room temperature ferromagnetic behavior with Curie temperature at or above the room temperature. The highest specific capacitance achieved via cyclic voltammetry in three-electrode system was 74.10 F/g at the scan rate of 5 mV/s. It has remarkable specific capacitance retention of ~ 95% after 5000 chargingdischarging cycles at the current density of 6 A/g. The energy storage parameters i.e., energy density and power density were ~ 3.93 Wh/kg and ~ 810.03 Wkg−1, respectively at current density of 1 A g−1.