MICROSTRUCTURE, ELECTRICAL-CONDUCTIVITY, AND PIEZOELECTRIC PROPERTIESOF BISMUTH TITANATE

A study was conducted on the effects of microstructure, atmosphere, an d several dopants on the electrical conductivity of bismuth titanate ( Bi4Ti3O12, BIT), Increased grain size increased the conductivity in un doped BIT as did acceptor dopants that substituted for either Bi (Ca a nd Sr) or Ti (Fe), A donor dopant (Nb) decreased the conductivity in B IT by as much as 3 orders of magnitude, The increased resistivity of N b-doped BIT improved the polarization in an electric field, A piezoele ctric coefficient, d(33), of 20.0 pC/N was achieved with a Nb-doped BI T composition corresponding to Bi4Ti2.86Nb0.14O12.