The effect of rare earth Dy3+ ions on structural, dielectric and electrical behavior of new nanocrystalline PbZrO3 perovskites

Dy3+ metal ions doped nanocrystalline lead zirconate perovskite with nominal composition Pb1−1.5xDyxZrO3 (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 1×106 to 1×109 Hz at room temperature. The decreasing trend in dielectric characteristics was observed with the incorporation of Dy3+ metal ions in PbZrO3 and also in these dielectric parameters, the damping effect was observed due to the replacement of Pb2+ ions with Dy3+ 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 Dy3+ ions in PbZrO3 nanocrystals. The current voltage (I-V) measurements depicted the increase in DC-electrical resistivity with increase of Dy3+ content in lead zirconate. The minimum and maximum resistivities were observed as 1.315×1011 Ω cm for PbZrO3 and 2.206×1011 Ω cm for Pb0.955Dy0.03ZrO3 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.