Local piezo-response for lead-free Ba_0.9Ca_0.1Ti_0.9Zr_0.1O₃ electro-ceramic by switching spectroscopy

The purpose of this work is to determine the effective piezoelectric coefficient (d₃₃) and the macro ferroelectric hysteresis behavior for the Ba_0.9Ca_0.1Ti_0.9Zr_0.1O₃ (BCZT). The sample was prepared by the modified Pechini method and it was sintered at 1250 ºC for 5 h. The refinements of X-ray diffraction (XRD) patterns obtained by the Rietveld method suggest a slight degree of tetragonality (c/a = 1.0025) in the perovskite structure. High counting statistics was performed in the two-dimensional grazing incidence 2D-GIXRD characterization by using synchrotron radiation. These results and the Raman spectrum analysis support the XRD interpretation. The morphology reveals a non-homogeneous terrace-type shape with a grain size distribution centered at 13 microns. The switching spectroscopy piezo-response force microscopy was used to obtained the effective d₃₃ = 142 pm/V. The soft ferroelectric hysteresis shows a coercive field H_c = 1.3 kV/cm with a saturation polarization P_s = 15.7 µC/cm².

Keywords:
Perovskite; Tetragonal; Piezo-response; Ferroelectric properties