本文研究目的是了解纳米二氧化钛对RTV涂膜半导体导电行为的影响规律。本文采用电位-电容法结合Mott-Schottky分析技术,研究了纳米二氧化钛对RTV涂膜在5%硫酸钠溶液中的导电行为影响。研究发现,添加纳米二氧化钛粉体,RTV涂膜Csc减小,其涂膜空间电荷层厚度增加。随着浸泡时间的延长,涂膜空间电荷电容Csc逐渐增加,表明涂膜中空间电荷层厚度随浸泡时间延长有逐渐减小趋势。添加纳米二氧化钛粉体,可促进RTV涂膜的导电行为由n型半导体导电特征转变为p型半导体导电特征,在添加量达2%时,转变为绝缘态。提出了RTV涂膜失效的半导体转变模型,纳米二氧化钛的作用正好与之相反。
The purpose of the paper is to realize the mechanism of Semiconducting transformation of RTV coating in the electrolyte. Pollution flashover is dangerous for super high voltage electric grid. Room temperature vulcanized (RTV) silicone rubber coating was an effect way of preventing pollution flashover for insulator utilizing in super high voltage grid because of its rigidity, adhesion, resistance, and having good performance of hydrophobic and hydrophobic transmission. On the basis of previous studies, an novel semiconducting behaviour of RTV coating was proposed. This paper studied the influence of nano TiO2 on the semiconducting conducting behaviour of RTV coating in the electrolyte. Potential-Capacitance method, combining with Mott-Schottky analysis, were utilized to study the influence of nano TiO2 on the conducting behaviour of RTV coating in 5% Na2SO4 solution. Results showed that adding nano TiO2 in RTV coating decreased its Csc, and increased its thickness of space charge layer. With increasing immersion time, the thickness of space charge layer of nano composite RTV coating might decrease. Adding nano TiO2 in RTV coating could make the RTV coating change from n-type to p-type semiconductor, then to an insulator while adding 2% nano TiO2. This paper also proposed a semiconducting transformation model for RTV coating degradation. It is suggested that the effect of nano TiO2 is just on contrary to the process of RTV degradation in the electrolyte.