Giant electro‐strain in textured Li+‐doped 0.852BNT–0.11BKT–0.038BT ternary lead‐free piezoelectric ceramics

Abstract

AbstractTexturing is an effective approach to improving the piezoelectricity of piezoelectric ceramics. In this work, <001> textured Li+‐doped 0.852Bi0.5Na0.5TiO3–0.11Bi0.5K0.5TiO3–0.038BaTiO3 ternary lead‐free piezoelectric ceramics are prepared by the reactive templates grain growth (RTGG) method. X‐ray diffraction (XRD) results demonstrate a high orientation degree of 77% along the <001> direction. Outstanding electro‐strain response, which is higher than most of reported BNT‐based textured ceramics, is achieved due to the contribution of oriented‐grains along the <001> direction. A large electro‐strain of 0.55% with a relatively low hysteresis is obtained at 6.5 kV/mm with corresponding large signal piezoelectric coefficient () of 846 pm/V in the textured ceramics, which is 49% higher than that of the random ceramics. Besides, the electro‐strain could reach as high as 0.52%@5.5 kV/mm ( = 945 pm/V) at 100°C. These results indicate that the RTGG is an effective way to design high performance lead‐free piezoelectric materials.