Pairing high piezoelectric properties and enhanced thermal stability in grain-oriented BNT-based lead-free piezoceramics

Abstract (Bi 0.5 Na 0.5 )TiO 3 (BNT)-based piezoceramics usually exhibit enhanced piezoelectric coefficient d 33 together with the deterioration of depolarization temperature T d , which is the common drawback limiting their use in practical application. Here, we demonstrate that harnessing the microstructure in BNT-based ceramics will be an efficient way to resolve this obstacle. oriented piezoelectric ceramics 0.94(Bi 0.5 Na 0.5 )TiO 3 −0.06BaTiO 3 was engineered by templated grain growth (TGG) using NaNbO 3 (NN) as templates. The manufactured textured ceramics with the optimized microstructure was characterized by not only approximately 200% enhancement in the magnitude of piezoelectric response ( d 33 ~297pC/N) but also improved thermal stability ( T d ~57 °C) in comparison to its randomly oriented counterparts ( d 33 ~151pC/N and T d ~32 °C). Moreover, the enhanced piezoelectricity in grain oriented specimens primarily originated from a high degree of non-180° domain switching as compared to the randomly axed ones. The current study opens the door to pair high piezoelectric properties and enhanced thermal stability in BNT-related materials though texture technique.