Structural, dielectric, conductive, and piezoelectric properties of a new three-layer Bi4−x/2Nax/2Ti3−xNbxO12 Aurivillius phase piezoceramics

A new three-layer Aurivillius phase piezoceramics, Bi[Formula: see text]Na[Formula: see text]Ti[Formula: see text]Nb[Formula: see text]O[Formula: see text] ([Formula: see text] = 0.01, 0.03, 0.05, and 0.10), were prepared by the traditional solid-state sintering method. All samples display a uniphase orthorhombic structure and plate-shaped grain. The introduction of Na/Nb inhibits the generation of oxygen vacancies, enhances dielectric stability and resistivity, and reduces dielectric loss. Increasing the Na/Nb amount could increase the activation energy [Formula: see text] and enhance the dc resistivity. The dc resistivity of Bi[Formula: see text]Na[Formula: see text]Ti[Formula: see text]Nb[Formula: see text]O[Formula: see text] [Formula: see text] ceramics has increased to above 10[Formula: see text] cm at 200 [Formula: see text]°C and 10[Formula: see text] cm at 500[Formula: see text]°C. The conduction mechanisms of the Bi[Formula: see text]Na[Formula: see text]Ti[Formula: see text]Nb[Formula: see text]O[Formula: see text] ceramics are also sufficiently explored. The conducting carriers are mainly oxygen vacancies, and their migration exhibits temperature-dependent relaxation characteristics. The Bi[Formula: see text]Na[Formula: see text]Ti[Formula: see text]Nb[Formula: see text]O[Formula: see text] ceramics obtain the excellent properties of high [Formula: see text]C, small [Formula: see text]C, low tan[Formula: see text]C = 0.2, large [Formula: see text]cm, and better [Formula: see text] pC/N. This work presents a valid tactic to design Aurivillius phase piezoceramics with enhanced resistivity and piezoelectricity for the field of high-temperature piezoelectricity.