Ba_(0.98)Bi_(0.02)(Ti_(0.9)Zr_(0.1))_(1-x)Cu_xO_3陶瓷的介电性能、弛豫行为与结晶化学特性

Dielectric Properties, Relaxor Behavior and Crystal Chemistry Properties of Ba_(0.98)Bi_(0.02)(Ti_(0.9)Zr_(0.1))_(1-x)Cu_xO_3 Ceramics

采用固相合成法,Bi3+作施主掺杂A位,Cu2+作受主掺杂B位,制备了Ba0.98Bi0.02(Ti0.9Zr0.1)1-xCuxO3(x=0,0.01,0.02,0.03)陶瓷样品。借助XRD、LCR等研究了该陶瓷的结构与介电性能。结果表明:当x=0.03时,陶瓷样品出现第二相。通过GULP模拟,缺陷偶极子的稳定性从低到高依次为:[2BiBa.+VBa″]、[2BiBa.+CuTi/Zr″]、[CuTi/Zr″+VO..],结合实验可知:介电弛豫程度与晶体中缺陷偶极子的存在形式相关,其中x=0.01时,晶体中以[2BiBa.+CuTi/Zr″]为主。随Cu2+掺杂量的增加,介电常数增加,介电常数与B位键价和呈反比变化、与八面体BO6的体积呈正比变化。

Ba0.98Bi0.02（Ti0.9Zr0.1） 1-xCuxO3 （x=0, 0.01, 0.02, 0.03） were prepared by conventional solid-state reaction methods. The effect of Bi3＋ as donor doping in A-site and Cu2＋ as acceptor doping in B-site on structure and dielectric properties were investigated by XRD, LCR and other techniques. The results revealed that when x = 0.03, the second phase occurred. The order of the defect dipoles stability from low to high is [2BiRa＋VBa]、[2BiBa＋CuTi/Zr]、[CuTi/Zr＋Vo] by GULP. Combined with the experiments, the analysis shown that the relaxation degree were closely related to the variety of defect dipoles, when x=0.01, the defect dipoles [2BiBa ＋CuTi/Zr] were dominant. With increasing Cu2~ content, the dielectric constants increased, and the dielectric constants were inversely proportional to the bond valance sum of B-site and proportional to the varieties of octahedral BO6 volume.