Vol.:(0123456789) 1 3 Journal of Materials Science: Materials in Electronics https://doi.org/10.1007/s10854-019-01977-8 Efect of the occupation of Pb and Ti sites on the structural, microstructural and dielectric properties of Y‑doped PbTiO 3 samples Mounir Belhajji 1  · Salaheddine Sayouri 1  · Aziz Nfssi 1  · Taj‑dine Lamcharf 2 Received: 7 June 2019 / Accepted: 2 August 2019 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract Pb 1−x Y x TiO 3 and PbY x Ti 1−x O 3 (x = 0, 2, 5, 8 and 10%) samples were produced using the sol gel process, and their structural, microstructural and dielectric properties investigated. X-ray difraction results show that a relatively low temperature of calcination of the undoped sample was sufcient to obtain the pure tetragonal structure without the presence of any second- ary phases, and that Y 3+ ions may occupy both Pb and Ti sites in the PbTiO 3 matrix. As a result of doping with Y 3+ ions into both Pb and Ti-sites, a strong reduction of the grain size of the undoped sample was revealed by Scanning Electron Microscopy analysis. Relatively high values of the dielectric permittivity were obtained under doping with Y into Ti-sites compared to those recorded under doping into Pb-sites as revealed by dielectric measurements. These values are higher in the case of low Y 3+ content. Moreover, dielectric measurements showed that the samples approach their frequency resonance, the latter depending on the temperature. 1 Introduction The tetragonal perovskite PbTiO 3 (PT),a well-known smart multiferroic material, is among the most typical perovskite ferroelectric with a high Curie temperature (490 °C) and a low dielectric constant of about 200 which makes it very attractive for high temperature and high fre- quency transducer applications [1–3] such as ultrasonic transducers, hydrophones, infrared sensors etc. It can be noticed that sintering of PT ceramics is very difcult due to their large tetragonality (c/a = 1.064); on cooling the strong anisotropy of the PT material generates internal stresses at the cubic-to-tetragonal transition and conse- quently the ceramic becomes fragile. However, addition of small concentrations of dopants results in an inhibition of cracking [4–7] through a reduction of the spontane- ous strain [4] or keeping the grain size very small [6, 7], and permitted successful poling to produce a piezoelectric efect. Diferent substituents [8–12] have been used to tailor properties of PT for specifc applications. Such substitutions have been shown to modify its ferroelectric and piezoelectric properties. In particular, doping with rare earth ions was reported to infuence dielectric parameters of PT such as the temperature of the ferro-to-paraelectric phase transition (FPPT) and the lattice anisotropy. Indeed, lowering of the FPPT was reported in Ln-doped PbTiO 3 ceramics (Ln = La, Ce, Sm) [13–15]. Moreover, doping with La 3+ was reported to ameliorate the planar coupling factor and to decrease both the cell volume and the c/a ratio [16]. Furthermore, the large piezoelectric ani- sotropy has been reported in ceramics modifed with Sm [17, 18]. Few studies have been devoted to the efect of doping with Yttrium on structural and dielectric properties of PT. Singh et al. [19] investigated microstructural, thermal and dielectric characteristics of Y modifed PT ceramics, where Y incorporated Pb sites. In particular, they have observed that crystallite and grain sizes increase with Y doping, and that the permittivity is sensitive to both the temperature and frequency parameters. Structural, dielectric, piezoelectric and ferroelectric behavior of lead titanate ceramics doped with Pr (x%) and Y (y%) with the chemical formula Pb 1−x Pr x Ti 1-y Y y O 3 where x = y = 0.02, 0.04, 0.06 and 0.08 revealed a non-uniform behavior of the FPPT and grain size as function of x (= y) * Salaheddine Sayouri ssayouri@gmail.com 1 LPTA, Fac. Sci. DM, USMBA, BP 1796, Fès-Atlas, Fes, Morocco 2 LSSC, Fac. Sci & Tech., BP 2202, Fes, Morocco