【摘要】 研究了Na2CO3对ZnO压敏材料电学性能的影响。当掺入的Na2CO3之摩尔分数x从0增加到0.2%时,ZnO压敏材料的击穿电压从209 V/mm增加到934 V/mm,1 kHz时的相对介电常数从1 158降到57。晶界势垒高度测量表明:在实验范围内,Na对势垒高度的影响较小。ZnO晶粒的变小是压敏电压急剧升高和介电常数减小的主要原因。对Na2CO3掺杂量的增加引起ZnO晶粒减小的原因进行了解释。更多还原

【Abstract】 The effect of Na2CO3 on the electrical properties of ZnO based varistors was investigated. The breakdown voltage of the ZnO based varistors increased from 209 V/mm to 934 V/mm and the relative dielectric constants decreased from 1 158 to 57 at 1 kHz when Na2CO3 concentration increases from 0 to 0.2 mol %. Measurement of barrier height at grain boundaries reveals that Na2CO3 concentration has less influence on barrier height in this experimental range. The ZnO grain size decreases when Na2CO3 concentration increases from 0 to 0.2 mol%. This is the substantial reason that causes the raise of breakdown voltage and decrease of relative dielectric constants. The reason is explained that ZnO grain size decrease when Na2CO3 concentration increases.更多还原