武康宁
我的新闻发布时间：2023-02-18
文章标题：恭喜博士生程卓林的文章在Journal of Advanced Ceramics发表
内容：
祝贺博士生程卓林的文章 Power loss transition of stable ZnO varistor ceramics: role of oxygen absorption on the stability of interface states at the grain boundary 在Journal of Advanced Ceramics发表。
Highly stable ZnO varistor ceramics with steadily decreasing power loss have been put into applications in electrical and electronic systems for overvoltage protections, even with the absence of general understandings on their aging behaviors. In this paper, we investigated their aging nature via conducting comparative dc aging experiments both in the air and in nitrogen, during which variations of electrical properties and interface properties were measured and analyzed. Notably, continuously increasing power loss with severe electrical degradation was observed for the sample aged in nitrogen. The transition of power loss was found to be closely related to the consumption of the oxygen absorption at the grain boundary, which, however, could keep steady for the sample aged in the air. The density of interface states, which is crucial for pinning the potential barrier, was proved to decrease in nitrogen, but keep stable in the air. Therefore, it is concluded that the oxygen absorption at the grain boundary is significant for the stability of interface states, which further correlates to the long-term stability of modern stable ZnO varistor ceramics.
