Composition dependence of phase boundary and electrical properties in lead-free (K0.5Na0.5)(Nb0.96Sb0.04)O3–Bi0.5Na0.5ZrO3–Bi0.5Li0.5ZrO3 ceramics

Abstract

In this work, (K0.5Na0.5)(Nb0.96Sb0.04)O3–Bi0.5Na0.5ZrO3–Bi0.5Li0.5ZrO3 lead-free ceramics were fabricated by the conventional solid-state method, and effects of Bi0.5Li0.5ZrO3 on their phase structure and electrical properties were studied. Their piezoelectric properties are sensitive to the addition of Bi0.5Li0.5ZrO3 as well as its contents. The addition of Bi0.5Li0.5ZrO3 simultaneously increased their Curie temperature and decreased rhombohedral and tetragonal phase transition temperature. Their dielectric, ferroelectric, and piezoelectric properties were strongly dependent on Bi0.5Li0.5ZrO3 contents. With increasing Bi0.5Li0.5ZrO3 contents, their dielectric loss can be decreased, and their k p and P r values can be further optimized. However, their e r and d 33 slightly decreased with the increase of Bi0.5Li0.5ZrO3 contents due to the deviation of rhombohedral and tetragonal phase boundary, and the ceramics with x ≤ 0.2 exhibited a high d 33 of >410 pC/N. As a result, this work could further understand the role of Bi0.5Li0.5ZrO3 in electrical properties of high-performance alkali niobate ceramics.