Effect of γ-rays irradiation on the structural, magnetic, and electrochemical properties of ZnMn2O4 nanoparticles

The study explored the effect of gamma-ray irradiation on the physical, magnetic, and electrochemical properties of ZnMn2O4 synthesized by the burning method. On the physical characterization side, the study utilized multiple metrology techniques to determine the impact of radiation dosage on bond lengths, density, crystallite size, micro strain, lattice constant, and dislocation density. No irradiation impact on the sample's tetragonal spinel structure was observed up to 250 kGy doses. However, the lattice parameters increased post-gamma-irradiation and were apparent in the morphology change of irradiated samples compared to control spinel. Conversely, the magnetic parameters decreased post-irradiation based on the vibrating-sample magnetometry (VSM) testing of control and gamma-irradiated samples. Changes in parameters like saturation magnetization (Ms) and magneton number (nB) can be attributed to ion-induced disorder and cation distribution in irradiated samples. Finally, the electrochemical testing showed supercapacitor behavior for all ZnMn2O4 samples, with a positive impact of radiation on electrical capacitance and stability. While the gamma-irradiated sample with a 250 kGy dose showed a capacitance (Csp) of 515 F/g with 87.6% stability, the control sample had a Csp of 123 F/g and 78% stability. ZnMn2O4 material meets the needs of energy storage devices operating at high ionizing radiation doses.