Microestructural and ferroelectric analyses of Pb₁₋₃ₓ/₂Laₓ(Zr₀.₅₄Ti₀.₄₆)₁₋₅ᵧ/₄NbᵧO₃ soft ceramics.

Microstructural and ferroelectric analyses were carried out on Pb₁₋₃ₓ/₂Laₓ(Zr₀.₅₄Ti₀.₄₆)₁₋₅ᵧ/₄NbᵧO₃ ceramics, x = y = 0.004, 0.006, 0.008 and 0.01 mol%. Using Piezoresponse Force Microscopy (PFM) and piezoelectric Hysteresis Loop (HL), ferroelectric behavior, and ferroelectric domain sizes were determined. Grain size (as determinate by SEM) and ferroelectric domain area decrease with the increase of dopant concentration from 3 μm to 1 μm and from 0.56 μm² to 0.32 μm², respectively. The maximum remnant polarization was obtained for Pb₀.₉₈₅La₀.₀₁Zr₀.₅₄Ti₀.₄₆)₀.₉₈₇₅Nb₀.₀₁O₃, showing that samples polarize easier with higher La³⁺ and Nb⁵⁺ dopant concentration. The coercive field does not show significant differences as the La and Nb content is varied. Grains tend to be single crystals as the La³⁺ and Nb⁵⁺ dopant concentration is increased.Análisis microestructural y ferroeléctrico de cerámicas suaves de Pb₁₋₃ₓ/₂Laₓ(Zr₀.₅₄Ti₀.₄₆)₁₋₅ᵧ/₄NbᵧO₃ Se realizaron análisis microestructurales y ferroeléctricos en cerámicas de Pb₁₋₃ₓ/₂Laₓ(Zr₀.₅₄Ti₀.₄₆)₁₋₅ᵧ/₄NbᵧO₃, x = y = 0.004, 0.006, 0.008 y 0.01% en moles. Se utilizó microscopía de fuerza de respuesta piezoeléctrica (PFM) y lazo de histéresis piezoeléctrica (HL), se determinó el comportamiento ferroeléctrico y el tamaño de dominio ferroeléctrico. El tamaño de grano (determinado por SEM) y el área del dominio ferroeléctrico disminuyen con el aumento de la concentración del dopante de 3 μm a 1 μm y de 0,56 μm² a 0,32 μm², respectivamente. La máxima polarización remanente se obtuvo para Pb₀.₉₈₅La₀.₀₁Zr₀.₅₄Ti₀.₄₆)₀.₉₈₇₅Nb₀.₀₁O₃, lo que demuestra que las muestras se polarizan más fácilmente con una mayor concentración de dopante La³⁺ y Nb⁵⁺. El campo coercitivo no presenta diferencias significativas ya que el contenido de La y Nb es variado. Los granos tienden a ser monocristales a medida que aumenta la concentración de los dopantes La3 + Nb5+

Determination of metal impurities in advanced lead zirconate titanate ceramics by axial view mode inductively coupled plasma optical emission spectrometry

An inductively coupled plasma optical emission spectrometry quantification method for the determination of Al, Ca, Cr Cu, Fe, Mn, Mg, Ni, Zn, Ba, K, In and Co in lead zirconate-titanate (PZT) ceramics, modified with strontium and chromium, was developed. Total digestion of ceramics was achieved with a HNO 3, H 2O 2 and HF (ac) mixture by using a microwave furnace. The sensitivity of the net signal intensity respect to radiofrequency power (P) and nebulizer argon flow (F N) variations was strongly dependent of the total excitation energy of line (TEE). For lines with TEE near metastable atoms and ions of argon, an increment of the sensitivities to P and F N variation was observed. At robust plasma conditions the matrix effect was reduced for all matrices and analytes considered. The precision of analysis ranged from 3 to 13%, whereas the analytes recoveries in the spiked samples varied, mostly, from 90 to 110%. The detection limits of studied elements were from 0.004 to 10 mg kg -1. © 2012 Elsevier B.V. All rights reserved.Peer Reviewe