Effects of Ag2O dopants on the piezoelectric properties of 0.94(K0.5Na0.5)NbO3-0.06LiNbO3 ceramics

Lead-free piezoelectric Ag2O-doped 0.94(K0.5Na0.5)NbO3-0.06LiNbO3 ceramics were investigated for their piezoelectric properties through use of a conventional sintering process. The effects of Ag dopants on the microstructure and the electrical properties of 0.94(K0.5Na0.5)NbO3-0.06LiNbO3 ceramics were systematically investigated. Ag dopants were added to 0.94(K0.5Na0.5)NbO3-0.06Li NbO3 ceramics at 1, 2, 3, 4, 5, 6, 7, and 8 mol%. X-ray diffraction analysis was performed to determine the structural properties and the lattice parameters. Piezoelectric constants and the temperature-dependent dielectric permittivity were measured. When the 7 mol% Ag2O-doped 0.94(K0.5Na0.5)NbO3-0.06LiNbO3 specimens were sintered at 1080 °C for 5 h, it showed the highest values of the density (4.32 g/cm3), the piezoelectric constant(d33) (274 pC/N) and the phase transition temperature Tc (465 °C).