Ferroelectric, piezoelectric, pyroelectric and Raman spectroscopy studies on BaTi0.9(Fe1/2Nb1/2)0.1O3 ceramic

The hysteresis, piezoelectric and pyroelectric properties were measured in the temperature range near the ferroelectric-paraelectric phase transition. The BaTi0.9(Fe1/2Nb1/2)(0.1)O-3 ceramic exhibits typical ferroelectric P-E hysteresis behavior with a remanant polarization, P-r, of about 7.52 mu C/cm(2) detected at 155 K. The electromechanical properties of this composition were measured using the resonance method. The ceramic provides high piezoelectric performance at the temperature of transition (T-max = 216 K): the piezoelectric constant is d(31) = 140 pC/N and the electromechanical coupling factor was k(P) = 22%. The pyroelectric study confirms the dielectric and ferroelectric measurements. The pyroelectric coefficient is about 125 nC/cm(2) K at T-max. Raman spectra of BaTi0.9(Fe1/2Nb1/2)(0.1)O-3 ceramic were taken at various temperatures and measured over the wave number range from 150 to 1300 cm(-1). (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim