Annealing temperature effect on structural, mechanical, and magnetic properties of Cd0.40M0.60ZnO2 (M = Mn, Ni) nanocomposites

We report here the effect of annealing temperature T-ann (200-600 degree celsius) on the structural, mechanical, and magnetic properties of Cd0.40M0.60ZnO2 (M = Mn, Ni) nanocomposites. The increase in Tann correlates with a significant change in unit cell volume (V), porosity (PS) crystallite size (D-hkl), particle size (r), Debye temperature (theta(D)) and elastic modulus (Y). The values of V, r, theta(D) and Y are higher for the Mn-series than Ni. While the values of PS and D-hkl are higher for Mn than Ni at T-ann <= 300 degree celsius, and the reverse is true at T-ann <= 400 degree celsius. The average particle size is 10.6 +/- 2.4 nm for Mn-series, but it is decreased to 7.5 +/- 4.0 nm for Ni-series, indicating quantum -dot size. Surprisingly, both series exhibit ferromagnetic behavior as Tann increases to 600 degree celsius, but the magnetization parameters for the Mn series are higher than those for Ni. Furthermore, the anisotropy field (H-a) is about 350 times higher than the corrective field (H-c), indicating hard magnetic materials. The switching field distribution (SFD) is increased by annealing, but it is higher for Ni-series than Mn. The considered nanocomposites would be useful for altering plastic deformation and spintronic devices.