Structural, optical and shielding properties of transition metals (R: Mg, Sn and Bi) doped nano ZnMn2O4: A comparative study

ZnMn2O4 and ZnMn1.9R0.1O4 (RMg, Sn, Bi) samples were formed using the sol-gel approach. Synchrotron diffraction equipment and FT-IR spectroscopy were used to investigate the structure and microstructure properties of different samples. The investigated structural properties include phases formed, crystallite size, cation distribution, lattice parameters, quadratic elongation, bond angle variance and vibrational bands. SEM technique was applied to investigate the surface morphology of all samples. The lowest reflectance was observed as ZnMn2O4 doped with Bi. Samples that have been doped with either Mg or Bi demonstrate an increased ability to capture daylight. Doped samples display a highest direct optical band gap (Eg) value of 2.91 eV when ZnMn2O4 doped with Sn, and a lowest Eg value of 2.44 eV when it doped with Bi. The computed refractive index (n) values from the various models and the average n-values for all samples are also examined. The highest n value and nonlinear optical parameters were observed as ZnMn2O4 doped with Bi. Doped samples containing Sn or Bi exhibit the highest values of linear attenuation coefficient (LAC) and mass attenuation coefficient (MAC) values in the lower and very high photon energy ranges. The sample doped with Sn exhibits the highest LAC and MAC values within the range of photon energies in the middle range. As ZnMn2O4 was doped with Mg, the half-value layer (HVL) and tenth value layer (TVL) values decreased marginally, but they decreased significantly when it doped with Bi or Sn. The doped samples exhibit a higher rate of photon absorption for lower energy photons compared to higher energy photons. In comparison to the undoped sample, the effective nuclear charge (Zeff) values of the doped samples are higher. The doped sample with Sn has the highest Zeff values. ZnMn2O4 and ZnMn1.9Mg0.1O4 samples demonstrate superior neutron shielding properties. The Exposure Buildup Factor (EBF) and Energy Absorption Buildup Factor (EABF) values showed a little alteration in response to the insertion of Mg in ZnMn2O4 matrix while they revealed significant variation as ZnMn2O4 doped with either Bi or Sn.