Enhancement of Piezoelectric and Ferroelectric Response via Tunning of Relaxor and Anti-Ferroelectrics: Insights from Poling Study

Abstract

The article presents a strategy to boost the electromechanical properties of Ti-based solid solutions with the NN antiferroelectric phase. Effect of NN on structural, dielectric, electric field reliant (the poling field (E_P) from 10 to 50 kV/cm) piezoelectric coefficient (d₃₃), electromechanical coupling constant (k_p), polarization, and strain properties were thoroughly investigated. The microstructural analysis highlighted that an optimal grain size distribution and phase purity are crucial for achieving superior piezoelectric performance. Notably, when the NN content reached 0.2 mol (2 NN), the NKBT ceramics exhibited exceptional electrical properties, including a dielectric constant of approximately 3727, a dielectric loss (tanδ) of 0.0228 at 100 kHz, and a high remanent polarization (P_r) of 60 μC/cm². Our findings also revealed optimized poling parameters at E_P = 50 kV/cm, yielding a high piezoelectric coefficient of 132 pC/N and the electromechanical coupling factors of 0.43 (k_p) in 2 NN with a high dielectric constant of ≈ 3644, a dielectric loss (tanδ) of 0.0299 in 100 kHz frequency. Moreover, a significantly large recoverable energy storage density of 0.512 J/cm³ was observed in 1 NN at a moderate electric field of approximately 98 kV/cm. This approach to enhancing insulating properties through NN modification has likely advanced our understanding of improving material properties for designing high-performance NKBT-based materials appropriate for sensors as well as energy harvesting requests in lead-free ferroelectrics.