Effects of Zn content on the magnetic and magnetocaloric properties of Ni-Zn ferrites

Abstract

Among spinel ferrites, Cd and Zn ferrites are always normal ferrites with Cd and Zn ions locating only in tetrahedral sites. This study presents effect of Zn on the magnetic and magnetocaloric properties of the mixed spinel ferrites Ni1-xZnxFe2O4 (x = 0.60, 0.65, 0.70, 0.75). The presence of Zn affects lattice parameters, saturation magnetization Ms, Curie temperature, Tc, and magnetic entropy change DSm. At highest Zn content, Tc reduces to the temperature lower than room temperature and magnetic structure of spins in the octahedral sublattice should be strongly canted. The maximum magnetic entropy change occurs in a large temperature range from low temperature to hundreds of Celcius degrees.