A suitable approach to achieve functional (Bi, Na)TiO3-based lead-free piezoceramics via compositional design for energy storage applications

In this work, sodium bismuth titanate based lead-free piezoceramics with modifiable dielectric and energy storage properties by compositional modification through Nb doping (0.94Bi(0.5)Na(0.5)TiO(3)-0.06BaTiO(3)-xNb(2)O(5)) were obtained. Nb doping on 0.94Bi(0.5)Na(0.5)TiO(3)-0.06BaTiO(3)-based ceramics produces a bifunctional behavior, which is governed by controlling the structural and microstructural characteristics of the system. Whereby the incorporation of Nb+5 leads to a change from rhombohedral-tetragonal (R-T) multiphasic coexistence to a tetragonal (T) phase at room temperature (RT) and causes a decrease in average grain size. The particularly high piezoelectric coefficient (d(33)), in the R-T multiphase coexistence region, facilitates the polarization and leads to a higher piezoelectric response than in the T-region. Meanwhile, increasing the Nb content improves the energy storage properties and results in a storage of energy value (W-rec) up to about 0.50 J/cm(3) at room temperature.

Automated summary

Sodium bismuth titanate based lead-free piezoceramics with modified dielectric and energy storage properties were obtained by doping Nb. The doping of Nb changes the material structure and microstructural characteristics, resulting in a transition from multiphasic coexistence to a single phase, and improving the piezoelectric response and energy storage properties of the material.