Impedance spectroscopy study of BNKLT polycrystalline ceramic |
| |
Authors: | Email author" target="_blank">K?Ch?Varada?RajuluEmail author B?Tilak K?Sambasiva?Rao |
| |
Institution: | (1) Department of Physics, Electronic Materials Research Laboratory, Mar Ivanios College, Thiruvananthapuram, Kerala, 695015, India;(2) Center for Ceramic Processing, ARC International, Balapur, Hyderabad, AP, 500005, India;(3) Department of Physics, St.John’s College Anchal, Kollam, Kerala, 91306, India;(4) International Advanced Research Institute for Powder Metallurgy and Material Processing(ARCI), Balapur, Hyderabad, A.P, 500005, India; |
| |
Abstract: | Complex impedance analysis of perovskite structured polycrystalline, Bi0.5(Na1−x−y
K
x
Li
y
)0.5]TiO3, at x=0.2, y=0.1 ceramic was synthesized by a mixed oxide method. The formation of single-phase material was confirmed by X-ray studies,
and it was found to be rhombohedral structure at room temperature. Under scanning electron microscope, grains separated by
well-defined boundaries are visible, which is in good agreement with impedance analysis. The BNKLT ceramic shows excellent
piezoelectric properties and the optimum properties measured are: d
33=251 pC/N, g
33=24×10−3 mV/N, k
p
=30.5% and k
t
=28.1%. A complex impedance spectroscopy (CIS) study has been carried out to investigate the electrical properties. Impedance
and modulus plots helped to separate the grain and grain boundary to the overall polarization or electrical behavior. CIS
analysis suggests the presence of temperature-dependent relaxation process in the material. A possible hopping mechanism for
electrical transport processes in the studied material is evident from the modulus analysis. The modulus mechanism indicates
the non-Debye type of conductivity relaxation in the materials, which is supported by impedance data. The activation energies
have been calculated from impedance (E
τ
=0.58 eV) and electric modulus (E
τ
=0.40 eV) studies, which suggests that the conduction is ionic in nature. The variation in width of the curves, M"/M"maxM'/M'_{\max} and Z"/Z"maxZ'/Z'_{\max} at FWHM, allows to conform that the relaxation process involved is of non-Debye type. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|