Effect of heterogeneous and homogeneous reactive templates on microstructures and piezoelectric properties of [001]-textured PMN-28PT piezoelectric ceramics

In this study, 3 vol% plate-like BaTiO₃ (BT) heterogeneous templates and PbTiO₃ (PT) homogeneous reactive templates were used, respectively, to fabricate [001]_C-textured 0.72Pb(Mg_1/3Nb_2/3)O₃-0.28PbTiO₃ (PMN-28PT) ceramics via the templated grain growth method. The texture development and microstructural evolution of textured piezoelectric ceramics were studied. BT-templated textured ceramics achieved a texture degree of 96 %, while PT-templated textured ceramics exhibited an increased texture degree of up to 99 % along the < 001 >_C direction. Textured piezoelectric ceramics fabricated using BT templates exhibited a piezoelectric coefficient (d₃₃) of 780 pC/N and a dielectric constant (ε_r) of 2638. In contrast, PT-templated textured PMN-28PT ceramics demonstrated superior piezoelectric and dielectric properties (d₃₃∼1110 pC/N, d₃₃*∼1356 pm/V and ε_r∼3041), and a large energy harvesting figure of merit (FOM) d₃₃×g₃₃ of 45.78 × 10⁻¹² m²/N. The inferior performance of hetero-textured ceramics is attributed to stress-clamping effects caused by residual BT templates. These results demonstrates that homo-templated textured PMN-28PT piezoelectric ceramics fabricated using PT homogeneous reactive templates are promising candidates for achieving high piezoelectric performance.