Microstructure and electrical properties of Bi1/2Na1/2TiO3–BaTiO3–Y2NiMnO6 lead-free piezoelectric ceramics

Lead-free ceramics (1−x−y) Bi1/2Na1/2TiO3–xBaTiO3–yY2NiMnO6 (BNT–BT–YNMO–x/y) were prepared by conventional solid-state reaction method and their structure and electrical properties were systematically investigated. The X-ray diffraction patterns showed that all the samples exhibit a pure perovskite phase with rhombohedral structure. All the modified ceramics with a clear grain boundary and uniformly distributed grain size were observed in SEM images. Either increasing x or y content can enhance ferroelectric and piezoelectric properties. The optimum electrical properties can be obtained at x=0.065 and y=0.002, which are as follows: Pr=38.05 μC/cm2, Ec=21.42 kV/cm, d33=219 pC/N and kp=29.5%. The results indicate that the BNT–BT–YNMO–x/y ceramics are promising lead-free piezoelectric candidates for practical applications.