Defect dipole polarization mechanism in low-dimensional europium substituted Al0.8La0.2TiO3 nanostructures

Abstract Low-dimensional Europium substituted Al0.8La0.2TiO3 (Al0.8EuyLa0.2-yTiO3 (y = 0.01–0.04))/AELTO nanostructures were prepared via hydrothermal method. The X-ray diffraction (XRD) patterns revealed the mixed phase (tetragonal and orthorhombic) structure of AELTO. Furthermore, the surface morphology evidenced the formation of AELTO nanostructures. The wide optical band gap (Eg) was achieved for y = 0.01–0.04 contents and found to be varying from 3.371 to 3.399 eV. The high dielectric constant (e′) values of 2.84 × 108 at 10 kHz and 101608.8 at 1 MHz were obtained for y = 0.02 at room temperature due to defect dipoles. In addition, the high ac-electrical conductivity (σac) of 15.78 S/cm (at 10 kHz) was observed at room temperature. The frequency dependence of dielectric modulus and impedance parameters was elucidated. The reverse arc present in the Cole-Cole plot of y = 0.02 content clearly suggested the presence of defect dipoles in AELTO.