The effect of rare earth Dy 3+ ions on structural, dielectric and electrical behavior of new nanocrystalline PbZrO 3 perovskites

Dy 3+ metal ions doped nanocrystalline lead zirconate perovskite with nominal composition Pb 1−1.5x Dy x ZrO 3 (x=0, 0.01, 0.02, 0.03, 0.04 and 0.05) were fabricated by wet chemical micro-emulsion technique. The annealing of all the samples was done at 700 °C for 3 h. The prepared nanocrystalline powder was characterized by different techniques such as X-ray powder diffraction (XRD), Fourier transforms infra-red spectroscopy (FTIR), dielectric response and dc-electrical resistivity. The powder XRD pattern confirmed the development of orthorhombic perovskite structure and the size of crystallite was calculated in the range of 45–135 nm. The lattice parameters and the crystallite size were demonstrated a nonlinear trend. The FTIR spectra were represented the intrinsic cation's vibration in the characteristic perovskite orthorhombic structure which observed in the range of 500−4000 cm −1 . The dielectric properties of all the prepared samples were measured in the range of 1×10 6 to 1×10 9 Hz at room temperature. The decreasing trend in dielectric characteristics was observed with the incorporation of Dy 3+ metal ions in PbZrO 3 and also in these dielectric parameters, the damping effect was observed due to the replacement of Pb 2+ ions with Dy 3+ ions in the region of higher frequency. The ac conductivity was measured in the range of 6.94×10 −5 –2.73×10 −5 (Ω cm) −1 by using dielectric results at 1.5 MHz frequency. Such results revealed that the ac conductivity have decreasing behavior with the doping of Dy 3+ ions in PbZrO 3 nanocrystals. The current voltage (I-V) measurements depicted the increase in DC-electrical resistivity with increase of Dy 3+ content in lead zirconate. The minimum and maximum resistivities were observed as 1.315×10 11 Ω cm for PbZrO 3 and 2.206×10 11 Ω cm for Pb 0.955 Dy 0.03 ZrO 3 nanocrystals, hence two fold increase in DC-electrical resistivity was found. The dominating influence of doping on dielectric and electric parameters is highly encouraging for the manufacturing of high frequency memory devices.