SYNTHESIS AND PROPERTIES OF NIOBIUM-, COBALT-SUBSTITUTED SOLID SOLUTIONS OF BISMUTH TITANATE WITH LAYERED PEROVSKITE STRUCTURE

A I Klyndyuk,A A Glinskaya,E A Chizhova

doi:10.29235/1561-8331-2018-54-2-154-160

Abstract

The Bi4Ti3–2xNbxCoxO12 (x = 0.05, 0.10, 0.15) solid solutions have been synthesized using ceramic method, their crystal structure, thermal expansion, electrical and dielectric properties have been studied. It has been established that Bi4Ti3–2xNbxCoxO12 titanates are p-type semiconductors whose electrical conductivity at low temperatures is higher, but at high temperatures is lower than for the base Bi4Ti3O12 bismuth titanate. It has been found that partial co-substitution of titanium by niobium and cobalt in Bi4Ti3O12 leads to the increase in the size of the unit cell of the Bi4Ti3–2xNbxCoxO12 solid solutions, a decrease in their Curie temperature, a decrease in the dielectric constant and dielectric losses, and slightly affects the magnitude of their linear thermal expansion coefficient. For Bi4Ti3.8Nb0.1Co0.1O12 and Bi4Ti3.7Nb0.15Co0.15O12 solid solutions, a sharp increase in the activation energy of electrical conductivity has been observed at the transition from the ferroelectric region to the paraelectric region.

Highlights

The Bi4Ti3–2xNbxCoxO12 (x = 0.05, 0.10, 0.15) solid solutions have been synthesized using ceramic method, their crystal structure, thermal expansion, electrical and dielectric properties have been studied
It has been established that Bi4Ti3–2xNbxCoxO12 titanates are p-type semiconductors whose electrical conductivity at low temperatures is higher, but at high temperatures is lower than for the base Bi4Ti3O12 bismuth titanate
It has been found that partial co-substitution of titanium by niobium and cobalt in Bi4Ti3O12 leads to the increase in the size of the unit cell of the Bi4Ti3–2xNbxCoxO12 solid solutions, a decrease in their Curie temperature, a decrease in the dielectric constant and dielectric losses, and slightly affects the magnitude of their linear thermal expansion coefficient

Summary

Introduction

The Bi4Ti3–2xNbxCoxO12 (x = 0.05, 0.10, 0.15) solid solutions have been synthesized using ceramic method, their crystal structure, thermal expansion, electrical and dielectric properties have been studied. В настоящей работе изучено влияние совместного замещения титана в Bi4Ti3O12 ниобием и кобальтом на кристаллическую структуру, тепловое расширение, термо-ЭДС, электропроводность и диэлектрические свойства твердых растворов Bi4Ti3–2xNbxCoxO12 Идентификацию образцов и определение параметров их кристаллической структуры осуществляли с помощью рентгенофазового анализа (РФА)

Results

Conclusion