Dysprosium-substitution induced changes in the structure and optical properties of nickel ferrite (NiFe2O4) thin films

► Effect of Dy-ion on the structure and properties of Ni-ferrite is investigated. ► Partial substitution of Fe3+ by Dy3+ expands the lattice. ► Grain-size increases with increasing annealing temperature. ► Direct correlation between structure and optical properties is derived.