Dielektriniai ir pjezoelektriniai batio3-pbzn1/3nb2/3o3 keramikų tyrimai /

Recently, considerable amount of research has been dedicated to ferroelectric oxides because of their application in various electronic devices. Ferroelectric oxides epitomize excellent dielectric and piezoelectric properties. Barium titanate (BT) is one of the widely used materials in electronics. BT can be doped with various different ions to modify its electrical properties for different applications. In this paper a relaxor PbZn1/3Nb2/3O3 (PZN) was added to ferroelectric solid solution to alter BT characteristics. In order to further deepen the knowledge about relaxors and their interaction with ferroelectrics, this research focuses on investigation of barium titanate doped with lead zinc niobate ((1–x)BaTiO3-xPbZn1/3Nb2/3O3). During the study dielectric and piezoelectric properties of four different concentrations x will be analyzed: x = 0, 0.05, 0.125, 0.15. Ceramics were investigated in the 20 Hz – 300 MHz frequency range and 120 K – 500 K temperature interval. 20 Hz – 1 MHz frequency range was measured using LCR HP4284A meter. Whilst for the higher frequency 1 MHz – 300 MHz band, a coaxial line was utilized and the complex reflection coefficient was measured using Agilent RF network analyzer 8714ET. The polarization and strain response was recorded by applying a high voltage signal using AixACCT TF 2000 analyzer equipped with a single-beam laser interferometer. The measurements of complex dielectric permittivity were carried out during the cooling cycle at a slower than 1 K/min temperature decline pace. Piezoelectric, dielectric and ferroelectric behavior of BT-PZN ceramics were characterized. It can be concluded that contrary to the expectations, BT doped with lead zinc niobate has worse dielectric properties. Phase transitions of doped materials are observed at the same temperatures as pure barium titanate. It was confirmed that studied materials undergo first order phase transition. Poled BT has piezoelectric resonances, materials doped with PZN could not be poled. At room temperature, PZN-doped materials have higher dielectric constant values. Doping of barium titanate with PZN did not improve piezoelectric properties, electrostrictive response is observed in PZN doped samples.

Grantor dc:publisher

Institutional Repository of Vilnius University

Year dc:date

2024

Author dc:creator

• Lapienytė, Patricija,

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

lit

Repository record dc:identifier

https://repository.vu.lt/VU:ELABAETD210579789&prefLang=en_US

OAI identifier oai:identifier

oai:vu.lt:elaba:210579789