Abstract
A distinct positive temperature coefficient of resistance (PTCR) effect had been found in (Bi1/2Na1/2)TiO3 (BNT)-added BaTiO3 (BT) ceramics prepared by a wet-chemistry route. The effects of Mn dopant on the microstructure and PTCR effect of BT-BNT ceramics were investigated. Small amount of Mn dopant not only decreased the resistivity of room temperature but also increased the PTCR jump. The resistivity of the Mn-doped BNT-BT ceramics was also analyzed using an a.c. complex impedance spectroscopy to reveal the origin of the PTCR effect. The mechanism of PTCR effect in Mn-doped BT-BNT ceramics was also discussed.
