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Abstract: Complex impedance spectroscopy (CIS) technique is used to obtain the electrical parameters of polycrystalline samples of Pb(Zr0.65−x Ce x Ti0.35)O3 (PZCT) (x =0, 0.05, 0.10, 0.15) in a wide frequency range at different temperatures. These samples were prepared by a high temperature solid-state reaction technique and their single phase formation was confirmed by X-ray diffraction technique. This study was carried out by the means of simultaneous analysis of impedance, modulus, and electrical conductivity. The Nyquist plots suggest that only the bulk is responsible in the conduction mechanism of the materials. The occurrence of single arc in the complex modulus spectrum of all the compositions of Ce confirms the single-phase characteristics of the PZCT compounds, and also confirms the presence of non-Debye type of multiple relaxations in the material. [Copyright &y& Elsevier]

A high-temperature solid-state reaction technique was used to prepare the polycrystalline samples of Cerium (Ce) modified lead zirconate titanate with Zr/Ti ratio 65:35 (i.e., Pb(Zr0.65-xCexTi0.35)O3 (PZCT)). Preliminary X-ray structural analysis exhibits the formation of the new compositions of PZT. In order to study the compositional effects on the electrical properties (complex impedance Z*, complex modulus M*, electrical conductivity and relaxation mechanisms) of PZCT, a nondestructive experimental technique (i.e., complex impedance spectroscopy) was used. The complex impedance analysis with Nyquist plots shows that the impedance parameters of all the PZCT samples contain bulk effect. The presence of single arc in the complex modulus spectra of PZCT confirms the single phase of PZCT with high relaxation time. The asymmetric behaviour of semi-circular arcs and shifting of peaks suggest the existence of non-Debye (Cole-Cole) type of relaxation mechanism in the PZCT systems. [ABSTRACT FROM AUTHOR]

Abstract: The polycrystalline samples of Pb(Zr0.65− x Mn x Ti0.35)O3 (PZMT) (x=0, 0.05, 0.10, 0.15) were prepared by a high-temperature solid-state reaction technique. Detailed studies on the effect of compositional variation of manganese (Mn) on the electrical behavior (complex impedance Z*, complex modulus M*, electrical conductivity and relaxation mechanisms) of the PZMT systems have been carried out by a nondestructive complex impedance spectroscopy (CIS) technique at 400°C. The Nyquist plots suggest that the grains only are responsible in the conduction mechanism of the materials. The occurrence of single arc in the complex modulus spectrum of all the compositions of Mn confirms the single-phase characteristics of the PZMT compounds, and also confirms the presence of non-Debye type of multiple relaxation in the material. [Copyright &y& Elsevier]

The samples of chemical stoichiometry formula Pb(Zr 0.35-x Ce x Ti 0.65)O 3 , x = 0.00, 0.05, 0.10, 0.15 were synthesized by a standard solid state route of mixing (calcination at 950 °C and sintering at 1100 °C). The electrical properties of rare earth element, cerium (Ce) doped lead zirconate titanate (PZCT) ceramics were investigated using complex electrical impedance spectroscopy (CIS). Results of Nyquist plots suggested that the electrical properties of the prepared ceramics are mainly dominated by bulk effect. The effects arising from grain boundary and interface polarization components have negligible contribution on the electrical properties. At higher temperatures, these ceramics behave as semiconductor due to their negative coefficient of resistance response. Due to the substitution of 5% of Ce, PZT shows relatively a large value of impedance making it a useful material for the electronic applications. The analysis of the modulus formalism confirmed the occurrence of non-Debye kind of electrical relaxation phenomenon in the material. Further, the relaxation mechanism is found to be dependent on both temperature and Ce concentration. The magnitude of ac conductivity of the ceramics is very much reduced with the Ce substitution. The nature of conductivity spectra shows that all samples conform to Jonscher's power law. Image 1 • For the first time, 35/65 PZT has been modified by cerium. • Samples were prepared using solid state reaction technique. • The electrical response is mainly due to bulk effect. • Non-Debye relaxations is observed in the ceramics. [ABSTRACT FROM AUTHOR]