Electrical properties and relaxation behavior of Bi0.5Na0.5TiO3-BaTiO3 ceramics modified with NaNbO3

Electric conduction and dielectric relaxation behavior in (1—x)(Bi0.5Na0.5TiO3-BaTiO3)-xNaNbO3 ((1—x)(BNT–BT)–xNN) ceramics were investigated. All compositions showed negative temperature coefficient of resistance (NTCR) behavior. The bulk conductivity followed the Arrhenius law with Ea = 1.24–1.55 eV, which can be attributed to the electronic conduction. In the modulus (M′′-f) spectra, a peak and a shoulder were observed, corresponding to the bulk and polar nano regions (PNRs) response respectively. With the increase of either temperature or NN content, the shoulder gradually depressed and even disappeared. A correlation between the PNRs evolution and the relaxation behavior was constructed.