Hyperfine interaction measurements on ceramics: PZT revisited

TDPAC Studies of Local Defects and Phenomena in Ferroics and Multiferroics

“…phases [25]. Other reports associate the fraction with the presence of defects in the neighborhood of TDPAC probes [28] for the cubic phase, which occurs at high temperature.…”

“…TDPAC experiments using the probe 181 Hf( 181 Ta) in lead zirconate titanate were carried out as a function of temperature [25] for PbZr 1−x Ti x O 3 with x = 0.47 and x = 0.48. As mentioned in the corresponding reports [25], these compounds have various potentially very useful applications relating to radar, hydrophones, ultrasound, high-voltage sources, and micropositioners. The substitution of Zr 4+ with Ti 4+ in lead titanate can lead to the appearance of a ferroelectric phase with rhombohedral symmetry and decreased tetragonal distortion [26].…”

“…If the Zr content is increased, an orthorhombic antiferroelectric phase can also appear [26]. The TDPAC results found in [25] indicate high-frequency distribution rates between room temperature and 900 K, and it was speculated that this effect was related to the coexistence of monoclinic and tetragonal phases. For the sample with x = 0.48, the dynamic attenuation was also considered when fitting the spectra obtained at 973 K and room temperature.…”

“…Different reports have proposed different origins for the second local environment, and it has not been assigned to the Ti or Zr site. Guarany et al [25] argued that the presence of two fractions may demonstrate the coexistence of monoclinic + tetragonal phases, which would occur at the morphotropic phase boundary when x ≈ 0.50 and would separate tetragonal from rhombohedral phases [25]. Other reports associate the fraction with the presence of defects in the neighborhood of TDPAC probes [28] for the cubic phase, which occurs at high temperature.…”

Synthesis of PZT Ceramics by Sol-Gel Method and Mixed Oxides with Mechanical Activation Using Different Oxides as a Source of Pb

“…Despite the existence of different well established methods for the preparation of ferroelectric ceramics, the necessity of controlling stoichiometry, doping, grain size, porosity, the homogeneity of the obtained phases, the control of the particle size in submicrometric powders, the obtention of thin films through different techniques, as well as lowering costs of processing and utilization of low-toxicity reactives, make important the exploration of variants in synthesis methods (Charles et al, 1992, Gringber & Rappe, 2007, Hammer & Hoffman, 1998, Heywang etal., 2008Pontes et al, 2004). There are several routes reported in the literature for synthesis of ferroelectric PZT ceramics (Guarany et al, 2007, Legrand et al, 2007 with the subsequent densification by pressureless sintering in oxygen rich atmosphere. The mechanochemical process is based on mechanical energy (associated e.g.…”