掺杂对0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3陶瓷结构和电学性能的影响

Influences of Oxide Doping on Structure and Electrical Properties of the 0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3 Ceramics

用传统的固相反应法、通过铌铁矿预合成路线制备了1mol%ZnO、MnO2和CuO掺杂的0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3(0.7PMN-0.3PT)陶瓷。XRD分析表明掺杂的0.7PMN-0.3PT陶瓷都呈现纯三方钙钛矿结构。烧成的陶瓷具有较高的致密度,其中CuO掺杂的0.7PMN-0.3PT陶瓷达到理论密度的93.79%。掺杂的0.7PMN-0.3PT陶瓷都呈现宽化、弥散的介电响应峰,然而介电常数的频率色散现象明显减弱。CuO掺杂的0.7PMN-0.3PT陶瓷呈现优良的综合电学性能:介电常数最大值εm达到21000左右,剩余极化强度Pr达到27.49μC/cm2,压电应变常量d33达到548pC/N。

1mol% ZnO-,MnO_2-and CuO-doped 0.7Pb（Mg_（1/3）Nb_（2/3））O_3-0.3PbTiO_3（0.7PMN-0.3PT） ceramics were prepared by conventional solid-state reaction method via the columbite precursor technique.X-ray diffractometry（XRD） confirmed that the synthesized oxide-doped 0.7PMN-0.3PT ceramics are of pure rhombohedral perovskite structure.The sintered oxide-doped 0.7PMN-0.3PT ceramics exhibit a high relative density,and the CuO-doped 0.7PMN-0.3PT ceramics reach 93.79% of the theoretical density.All the oxide-doped 0.7PMN-0.3PT ceramics exhibit broad and diffused dielectric response peaks,whereas the frequency dispersion of the dielectric constant is suppressed greatly.The CuO-doped 0.7PMN-0.3PT ceramics exhibit excellent integral electrical properties,the value of dielectric maximum ε_m is around 21000,the remanent polarization P_r is 27.49μC/cm^2 and the piezoelectric constant d33 reaches to 548pC/N.