Abstracts Book - IMRC 2018

• SD6-P003
TEXTURE INFLUENCE ON THE ELECTRONIC STRUCTURE IN LEAD-
FREE PEROSVKITE ELECTRO-CERAMICS BASED ON Ba1-
xCaxTi0.9Zr0.1O3 BY HR-XRD AND MICRO-XANES
Guillermo M Herrera 1 , Jesus Canche 2 , Maria Elena Montero Cabrera 2 , Jasper Plaisier 3 , Diane
Eichert 3 , Luis E. Fuentes Cobas 4
1 Consejo Nacional de Ciencia y Tecnologia - CONACYT, Física de Materiales, Mexico. 2 Centro de
Investigación en Materiales Avanzados, S.C., Medio Ambiente, Mexico. 3 Elettra-Sincrotrone
Trieste, Physics, Italy. 4 Centro de Investigación en Materiales Avanzados, S.C., Física de
Materiales, Mexico.
Lead-free electro-ceramics belong to an important group of functional materials
with a wide range of applications including capacitors and transducers due to
their excellent piezo/ferro-response and dielectric properties. One of promising
electro-ceramic is the Ba 1-x Ca x Ti 0.9 Zr 0.1 O 3 because of its outstanding piezo/ferroreponse
among lead-free piezoelectric materials family. This work has the
purpose to monitor the structure and electronic structure evolution for Ba 1-
xCa x Ti 0.9 Zr 0.1 O 3 compounds prepared by the modified Pechini method and
sintered in a range of temperatures between 1200 up to 1400 o C at 5 h. High
resolution X-ray diffraction (HR-XRD) and micro-X-ray absorption near edge
spectroscopy (μ-XANES) experiments took place simultaneously in the 7.1 MCX
beamline and the 10.1L X-ray fluorescence, XRF beamline (with a photon energy
resolution of 0.5 eV) at the Elettra Sincrotrone Trieste. HR-XRD patterns show an
important contribution of texture (preferred crystal orientation) effects on the
phase structure as the Ca concentration increases. An intensity decreases of
(002/200) diffraction peak related to the tetragonal phase was observed for the
samples with x= 0.125, 0.16 and 0.18. The (004/400) diffraction peak was
measured with large number of counts in order to elucidate the splitting
associated to the tetragonal phase and then to monitor their evolution as we
change the Ca concentration. The experimental absorption spectra (Ti K-edge)
showed a white line around 4988 eV. Three main features in the pre-edge region
(4965-4985 eV) were observed. However, the intensity of the peaks and the
peaks shape varied among different spectra in this region, when the Ca
concentration was increasing. On the other hand, a decrease of relaxor-like
behavior was monitored during the analysis of the dielectric properties. The
evaluation of these properties complements the characterization of these
compositions. HR-XRD experiments performed in these compositions were
important to elucidate changes in the texture. The shape, intensity and position