Synthesis and fabrication of tetragonal copper chromite nanospheres for usage as the cathode material in asymmetric supercapacitors

Abstract

The rapid advancement of capacitive materials has necessitated the modernization of energy storage materials and it is crucial to continue enhancing spinel-structured functional materials in energy storage devices. The tetragonal CuCr₂O₄ spinel material, leads to the development of an electrochemical method for high-performance energy conversion, was first synthesized by different surfactants. Subsequently, their characteristics and morphology were abruptly changed with the introduction of different surfactants, which can be confirmed by the techniques. This CuCr₂O₄ material exhibits EDLC behaviour, according to electrochemical studies, but the material produced by the CTAB surfactant offers a higher specific capacitance due to its larger surface area, rougher surface, and more ion adsorption active sites due to its spherical morphology. CuCr₂O₄ with CTAB was used as the electrode material in a three-electrode configuration to achieve capacitance values of up to 965 F g⁻¹ at a scan rate of 1 A g⁻¹ and offers excellent cyclic stability of 91 % of the initial capacitance after 5000 cycles in 1 M Na₂SO₄ electrolyte. CuCr-4//AC, an asymmetric supercapacitors (ASC) device, provides a high energy density of 31.59 W h kg⁻¹ with power density of 948 W kg⁻¹ and a high specific capacitance of 89 F g⁻¹ at 0.5 A g⁻¹. Furthermore, at 0.5 A g⁻¹, the ASC maintains a high cycling stability of 88.3 % across 10,000 CV cycles, and hence CuCr₂O₄ nanospheres can be a promising electrode material for enhanced energy storage devices due to their better electrochemical performance.