Dielectric and magnetic variance in NiCo2O4 spinels mediated by Zn-substitution for efficient data and energy storage

The presence of multiferroic behaviour in any material makes it exceptionally important for its possible significant role in technological developments. The combination of dielectric and magnetic orders in a single device has become an intriguing topic for material scientists in recent days. In this context, sol‒gel auto-combustion technique was utilized to synthesize Zn-substituted NiCo2O4 to exploit its energy and data storage pursuits. Spinel-based cubic structure of metal cobaltites was affirmed using X-ray diffraction technique. Enhancement in grain size mediated by Zn substitution was visualized. Furthermore, elemental analysis confirmed the required stoichiometric contents in the samples. Koop’s theory, consistent with Maxwell–Wagner model, elaborated the decrease in dielectric constant by enhancing the frequency. An energy loss in dielectric relaxation was probed by measuring the loss tangent. In addition, the substitution of Zn also caused a decrease in resistive behaviour of the samples. Magnetic analysis revealed that when Ni was replaced with Zn, the saturation magnetization decreased which was attributed to the relative magnetic dipole moments of Zn and Ni.