Piezoelectric, magnetic and magnetoelectric properties of a new lead-free multiferroic (1-x) Ba0.95Ca0.05Ti0.89Sn0.11O3—(x) CoFe2O4 particulate composites
Résumé
New multiferroic particulate composites (1-x) Ba0.95Ca0.05Ti0.89Sn0.11O3-(x) CoFe2O4 with (x = 0.1, 0.2, 0.3, 0.4 and 0.5) have been prepared by mechanical mixing of the calcined and milled individual ferroic phases. X-ray diffraction and Raman spectroscopy analysis confirmed the formation of both perovskite Ba0.95Ca0.05Ti0.89Sn0.11O3 (BCTSn) and spinel CoFe2O4 (CFO) phases without the presence of additional phases. The morphological properties of the composites were provided by using field emission scanning electron microscopy. The BCTSn-CFO composites exhibit multiferroic behavior at room temperature, as evidenced by ferroelectric and ferromagnetic hysteresis loops. For all composites, the converse piezoelectric coefficient was calculated and found to decrease from 203 pm.V-1 to 27 pm.V-1 in pure BCTSn. when the CFO content increases. The magnetoelectric (ME) coupling was measured under a magnetic field up to 10 kOe and the maximum ME response found to be 0.1 mV.cm(-1).Oe(-1) for the composition 0.7 BCTSn-0.3 CFO exhibiting a high degree of pseudo-cubicity and large density.