Lead-free ferroelectric ceramics(1-x)BaTiO_(3-x)Bi(Mg_(1/2)Ti_(1/2))O_(3)(x=0.0-0.07)were synthesized by conventional solid state reaction method and the correlation of structure,dielectric,ferroelectric and impedance...Lead-free ferroelectric ceramics(1-x)BaTiO_(3-x)Bi(Mg_(1/2)Ti_(1/2))O_(3)(x=0.0-0.07)were synthesized by conventional solid state reaction method and the correlation of structure,dielectric,ferroelectric and impedance properties were investigated.It was found that T_(m) andε_(m) showed decreasing trend with the increase of BMT content.The high-temperature dielectric relaxation behaviour was observed in all the samples.The activation energy calculated from impedance(E_(a))and conductivity(E_(cond)),which revealed that the relaxation behaviours were linked with the migration of OVs.The values of E_(a)were almost equivalent to Econd.It was concluded that the short-range hopping of oxygen vacancy contributed to the dielectric relaxation and long-distance movement of doubly ionized oxygen vacancies contributed to the conduction.On the other hand,with increasing BMT contents,it was found that P-E loops became slimmer and slimmer,which indicated the increase of relaxor behaviour.The temperature dependence of P-E loops for 0.98BT-0.02BMT ceramic clearly showed the transition process from ferroelectric to relaxed ferroelectrics.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11574057 and 51604087)the Guangdong Provincial Natural Science Foundation of China(Grant No.2016A030313718)the Science and Technology Program of Guangdong Province of China(Grant Nos.2016A010104018,and 2017A010104022).
文摘Lead-free ferroelectric ceramics(1-x)BaTiO_(3-x)Bi(Mg_(1/2)Ti_(1/2))O_(3)(x=0.0-0.07)were synthesized by conventional solid state reaction method and the correlation of structure,dielectric,ferroelectric and impedance properties were investigated.It was found that T_(m) andε_(m) showed decreasing trend with the increase of BMT content.The high-temperature dielectric relaxation behaviour was observed in all the samples.The activation energy calculated from impedance(E_(a))and conductivity(E_(cond)),which revealed that the relaxation behaviours were linked with the migration of OVs.The values of E_(a)were almost equivalent to Econd.It was concluded that the short-range hopping of oxygen vacancy contributed to the dielectric relaxation and long-distance movement of doubly ionized oxygen vacancies contributed to the conduction.On the other hand,with increasing BMT contents,it was found that P-E loops became slimmer and slimmer,which indicated the increase of relaxor behaviour.The temperature dependence of P-E loops for 0.98BT-0.02BMT ceramic clearly showed the transition process from ferroelectric to relaxed ferroelectrics.
