室温固相化学法制备ZnO压敏电阻用纳米粉体及其压敏特性的研究

Preparation of Nano-Powders for ZnO Varistors by Solid-State Reaction at Room Temperature and Study on the Properties of ZnO Varistors

采用室温固相化学法,并通过对反应物摩尔配比、球磨时间、前驱物洗涤方式等因素的控制,合成了掺杂ZnO纳米粉体.借助XRD,TEM,粒度分布测试等手段,对粉体的组成、形貌和粒度进行了表征,探讨了反应条件对粉体性能的影响.结果表明,在反应物配比为1.10,球磨时间为30min,采用含量为3%的PEG-2000作为表面改性剂的条件下,制备了粒径为20nm左右、形状为球状的掺杂ZnO粉体.将制备的粉体通过成型,在1080℃制备了电位梯度为791.64V/mm、非线性系数为24.36、漏电流为43μA的压敏电阻.借助XRD,SEM,电性能测试等手段,对ZnO压敏陶瓷的组成、结构及压敏电阻的性能进行了表征,探讨了工艺参数对压敏电阻性能的影响及其机理.

Through controlling the ration of regents, grinding time and the washing way of precursor, the nano-powders of doped ZnO were obtained by solid-state reaction at room temperature. The powders were determined by means of XRD, TEM and laser size analysis. And reaction factors were discussed. The results showed that sphery doped ZnO powder with 23nm can be synthesized when the ration of regents was 1.10 , ball-grinding time of 30min and PEG_ -2000 of 3% as surfactant. ZnO varistors were gained by sintering gre...