Effect of niobium doping on piezoelectric and pyroelectric properties of Bi3.5 Nd0.5 Ti3 O12 ceramics

摘要

Niobium-doped bismuth titanate (Bi 3.5-x/3 Nd 0.5 Ti 3-x Nb x O 12 , x = 0 to 0.09) were prepared using a conventional mixed oxide method, and the effects of Nb doping on the dielectric, ferroelectric, piezoelectric and pyroelectric properties of the ceramics were examined. In general, the doping with Nb decreases the relative permittivity , coercive field E c and leakage current density J of the ceramics, while increases the remnant polarization P r , piezoelectric (charge) coefficient d 33 and pyroelectric coefficient p. At 6 mol% Nb-doping level, the ceramic exhibit a large P r (15 C/cm 2 ) and a low J (3×10 -8 A/cm 2 ) under an electric field of 75 kV/cm, while its d 33 and p reach a maximum value of 22 pC/N and 129 C/m 2 K, respectively. Since the ceramic also has a relatively low value of 115 (hence a high value of piezoelectric (voltage) coefficient), it is a potential candidate for sensing applications.