Optimizing the Piezoelectric and Dielectric Properties of Pb(In1/2Nb1/2)O₃-PbTiO₃ Ferroelectric Crystals via Alternating Current Poling Waveform

The alternating current poling (ACP) method has been attracting significant attention because of the enhanced piezoelectric and dielectric properties of relaxor-based ferroelectric (FE) crystals with advantages of high-efficiency, time-savings, and ease of operation. The most commonly used poling waveform is the bipolar triangle. Other waveforms have been seldom applied in ACP. However, the waveform plays a significant influence on the fatigue performance of FE materials. Therefore, optimizing the ACP waveform to gain high piezoelectric performance and decrease dielectric loss factors is technologically essential. Here, the effects of ACP waveforms on the piezoelectric and dielectric properties of [001]
_c
-oriented 0.66 PIN-0.34 PT FE crystals were studied. The highest piezoelectric coefficient d
₃₃
(1450 pC/N) and dielectric permittivity ε
^T
₃₃
/ε
₀
(3180) were obtained using the sesquipolar triangle waveform while the lowest dielectric loss factors tan δ (0.99%) was obtained using the unipolar triangle waveform. FE hysteresis loop measurements revealed that the lower coercive field and current density are beneficial for higher piezoelectric performance. Domain analysis showed that ACP samples exhibit a regular domain structure and high density 109° domain walls, which are the critical reasons for enhanced piezoelectric performance. This work provides guidance in designing an ACP waveform to achieve higher performance.