室温固相合成掺杂ZnO纳米粉体制备ZnO压敏电阻

Preparation of Doped ZnO Nano-powders and ZnO Varistors by Solid-state Reaction at Room Temperature

以金属离子盐和草酸为原料,采用室温固相化学反应合成掺杂ZnO前驱物,根据DSC-TG分析结果,将其在450℃热分解2 h,得到掺杂ZnO粉体,并用此粉体制备了片式ZnO压敏电阻。借助XRD、TEM、BET等检测手段对粉体产物的物相、形貌、粒度等进行了表征。研究了烧结温度对ZnO压敏电阻电性能的影响。结果表明,所制备的粉体为平均粒径24 nm左右、颗粒呈球状、分散性好的纤锌矿结构掺杂ZnO。在1 080℃烧结时,ZnO压敏电阻的综合电性能达到最佳,电位梯度为791.64 V/mm,非线性系数为24.36,漏电流为43μA。

Using Zn （ NO3 ） 2· 6H2O, H2 C2O4 and additives of other metal salts as raw materials, ZnO precursor was synthesized by solid-state reaction at room temperature, and doped ZnO nano-powders were obtained by decomposing the precursor at 450 ℃ for 2 h. Then ZnO varistors were prepared at different sintering temperatures. The powders were determined by XRD, TEM and BET, and electric properties of ZnO varistors were discussed in detail. The results show that the doped ZnO nano-powders are spherical and dispersive, with grain size about 24 nm. The general electric properties of ZnO varistors sintered at 1 080 ℃ are the best： potential gradient 791.64 V/mm, nonlinear coefficient 24.36 and leakage current 43 μA.