Investigation on the effect of Dy doping on the microstructure, dielectric, electrical, and magnetic properties of Bi2/3Cu3Ti4O12 ceramic

Bi(2/3)-xDyxCu3Ti4O12, BDCTO ceramic with compositions x = 0.05, 0.10, and 0.20 as designated BDCTO-0.05, BDCTO-0.1 and BDCTO-0.2 respectively, were synthesized through semi wet route and at a sintering temperature of 1173 K for 8 h. The effects of A-site Dy-doping on the structure, magnetic, and dielectric characteristics of BCTO were investigated extensively. The X-ray diffraction pattern and Le-bail analysis reveal the occurrence of all the peaks of parent BCTO ceramic which confirm the formation of a single phase on doping of Dy up to composition 0.2 with the fine crystal structure. Further, it observed that the lattice parameter of the synthesized ceramics decreases with increasing Dy concentration. The phase space group Im-3 of the ceramics was determined by Le-bail analysis of X-ray diffraction data. The particle size of the BDCTO ceramics obtained from the transmission electron microscopy images was found in the ranges of 80-101 nm. The phase composition and conventional change in the microstructural properties of BDCTO ceramics were studied by X-ray diffraction and Scanning electron microscopy. The average grain sizes of the BDCTO-0.05, BDCTO-0.1 and BDCTO-0.2 ceramics were found to be 123.44 nm, 125.36 nm, and 132.11 nm, respectively. Oxidation state of various ions was studied using X-ray photoelectron spectroscopy. The dielectric permittivity and tangent loss of the BDCTO ceramic deceases with increasing frequency. Impedance analysis showed the evidence of the existence of the thermally assisted ionic phenomenon in ceramics. M-T and M-H curve shows the antiferromagnetic characteristics of the weak ferromagnetic or para magnetic behaviour of BDCTO ceramics.