Microstructure and magnetic properties of Y2/3Cu3Ti4O12 ceramic

Abstract

Y_2/3Cu₃Ti₄O₁₂ (YCTO) ceramic was prepared via the semi-wet route. Rietveld refinement of XRD peaks suggested a pseudo-cubic symmetry with the lattice parameter = 7.3775 Å and the space group Im (No. 204). The opted process of synthesis allowed Y³⁺ and Cu²⁺ ions to be placed at the respective theoretical sites within the acceptable occupancy range. Y³⁺ ions occupy the face and edge centred positions and Cu²⁺ ions occupy the corner and body centred positions of the cube. Y_2/3Cu₃Ti₄O₁₂ differs from CaCu₃Ti₄O₁₂ in which Ca²⁺ ions occupy the corner and body centred positions and Cu²⁺ ions occupy the face and edge centred positions of the cube. AFM studies revealed a platykurtic type of distribution of round shaped grains with the average size of 59 nm. The root-mean-square and average roughness of a homogeneous thin film of YCTO are estimated to be 2.288 and 1.854 nm, respectively. The magnetic studies establish that the YCTO ceramic remains in paramagnetic phase at 300 K, although it undergoes an antiferromagnetic to paramagnetic transition around its Neel temperature, T_N = 24.34 K.