An improvement in ferroelectric and ferromagnetic properties of low sintering-temperature (1-x)(0.98(Bi0.5(Na0.78K0.22)0.5-TiO3)-0.02CuO)-(x)NiFe2O4 particulate 0-3 composites

In this study, we report a detail investigation of structural, morphological, ferroelectric, and ferromagnetic properties of low sintering-temperature lead-free particulate composites of (1-x)(0.98(Bi-0.5(Na0.78K0.22)0.5-TiO3-0.02CuO)-xNiFe(2)O(4)(x = 0-0.15) by using some techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), ferroelectric hysteresis (P-E), piezoelectric constant (d(33)), and magnetization (M-H) measurements. The formation of two parent materials in single crystal phases without any impurities was demonstrated by XRD. It was interesting that the spontaneous ferroelectric polarization P-s increased with NFO content, reached maximum value at a concentration of 6 mol% of NFO in composite and then declined gradually with further increase of NFO content. Meanwhile, the maximum strain S-max, normalized strain S-max/E-max (d(33)*), and piezoelectric constant d(33) exhibited a gradual reduction as NFO content increased. In M-H hysteresis loop measurements, an improvement in saturation magnetization M-s as well as M-r was observed, albeit not proportional, indicating an increase in ferromagetism of composite.

Automated summary

In this study, the structural, morphological, ferroelectric, and ferromagnetic properties of low sintering-temperature lead-free particulate composites were investigated in detail. The XRD analysis demonstrated the formation of two parent materials in single crystal phases without impurities. It was found that the ferroelectric polarization, strain, and piezoelectric constant gradually decreased with the increase of NFO content in the composite, while the saturation magnetization and remanent magnetization in the M-H hysteresis loop measurements improved, indicating an increase in ferromagnetism of the composite.