Self-biased large magnetoelectric coupling in co-sintered Bi_(0.5)Na_(0.5)TiO_3 based piezoelectric and CoFe_2O_4 based magnetostrictive bilayered composite

摘要

In this work, magnetoelectric properties of a co-sintered bilayered composite of non-lead based piezoelectric 0.97(Bi_(0.5)Na_(0.5)TiO_3)-0.03(K_(0.47)Na_(0.47)Li_(0.06)Nb_(0.74)Sb_(0.06)Ta_(0.2)O_3) and magnetostrictive Co_(0.6)Zn_(0.4)Fe_(1.7)Mn_(0.3)O_4 are presented. Similar optimal sintering conditions of the individual components lead to a very clean interface as evidenced in the scanning electron microscopy, angle dispersive X-ray diffraction, and energy-dispersive X-ray (EDX) results. Clean interface results in strong intimate mechanical coupling between both components and causes a maximum transfer of induced strain, leading to a large magnetoelectric coupling ～142 mV/cm·Oe measured in longitudinally magnetized-transversely polarized configuration (L-T mode). Remnant polarization ～32 μC/cm~2, remnant magnetization ～0.50 emu/g, and sufficiently high self biased magnetoelectricity ～135 mV/cm Oe (L-T mode) were observed for this composite.