Structural and Electrical Properties of Er ₂ O ₃ ‐Doped Na _1/2 Bi _1/2 TiO ₃ Lead‐Free Piezoceramics

Abstract

Sodium bismuth titanates Na 1/2 Bi 1/2 TiO 3 (NBT) doped with 0–3 wt% Er 2 O 3 were prepared by the conventional solid‐state reaction method. The X‐ray diffraction results revealed that the sintered Er‐doped NBT ceramics exhibited a pure perovskite structure with Er 3+ concentrations ranging from 0 to 1 wt%. At a low Er 2 O 3 concentration, the Er‐doped NBT ceramics showed enhanced electrical properties with dielectric constant ɛ 33 T /ɛ 0 =636, a low dielectric dissipation factor (tan δ=3.3%), a low coercive field ( E c =4.56 kV/mm), and a high piezoelectric constant ( d 33 =75 pC/N). The relationship between the composition and properties of Er‐doped NBT ceramics has been discussed.