Remarkable Enhancement in Piezoelectric Performance of [001] Textured Na0.4K0.1Bi0.5TiO3 Ceramic

This study explores the dependence of dielectric and piezoelectric properties on the grain morphology, orientation, and electric field in the [001] textured Na0.4K0.1Bi0.5TiO3 (NKBT-T) piezoceramics, fabricated via reactive template grain growth and tape-casting methods. A high degree of [001] texturing with Lotgering factor (f) of ∼0.92 was confirmed by X-ray diffraction, electron backscattered diffraction, and bulk texture measurements. A large average plate length of ∼8.5±1 μm with an aspect ratio of ∼11 was achieved in NKBT-T ceramic. An extremely large value of piezoelectric voltage coefficient (g33) of ∼100×10−3 Vm/N was observed in poled NKBT-T ceramics, originating from a low dielectric constant (∼230) and high piezoelectric charge coefficient (d33 ∼205 pC/N). The transduction coefficient (d33•g33) of NKBT-T ceramic was estimated at ∼20000 × 10−15 m2N−1 and the mechanical energy harvesting responses of ∼1.8 µA and ∼4 V were recorded in the NKBT-T ceramic-based piezoelectric device.