Abstract
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 3h. 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 45–135nm. 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 500−4000cm−1. The dielectric properties of all the prepared samples were measured in the range of 1×106 to 1×109Hz 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(Ωcm)−1 by using dielectric results at 1.5MHz 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 1.315×1011Ωcm for PbZrO3 and 2.206×1011Ωcm 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.