Enhanced electrical properties of textured NBBT ceramics derived from the screen printing technique

(001)_pc-oriented (Na_0.5Bi_0.5)_0.94Ba_0.06TiO₃ (NBBT) lead-free piezoelectric ceramics were fabricated by the screen printing technique using Na_0.5Bi_0.5TiO₃ (NBT) templates. The plate-like NBT template particles were synthesized from bismuth layer-structured ferroelectric Bi₄Ti₃O₁₂ (BiT) precursors by the topochemical method. The screen printed NBBT ceramics with 20 wt% NBT templates contained a large fraction of grains aligned with their c-axis normal to the sample surface, giving a Lotgering factor of 0.486. The dielectric and ferroelectric properties of textured NBBT ceramics were anisotropic. Compared with the non-textured NBBT ceramics, the dielectric, ferroelectric, and piezoelectric properties of the textured NBBT ceramics were improved, giving a dielectric constant ε^T₃₃/ε₀ T of 910, a remnant polarization P_r of 29.2 μC/cm², a coercive field E_c of 23.5 kV/cm, a piezoelectric coefficient d₃₃ of 180 pC/N, and a thickness-mode electromechanical coupling coefficient k_tof 0.485.