为了解纳米二氧化钛(TiO2)对室温硫化(RTV)硅橡胶涂膜半导体导电行为影响的规律,采用电位-电容法结合Mott-Schottky分析技术研究了在硫酸钠的质量分数w(Na2SO4)=5%的硫酸钠溶液中纳米二氧化钛对RTV硅橡胶涂膜的导电行为的影响。研究发现,添加纳米二氧化钛粉体后,RTV硅橡胶涂膜的空间电荷层电容Csc减小,该涂膜的空间电荷层厚度增加。随着浸泡时间的延长,涂膜的空间电荷层电容Csc逐渐增加,表明涂膜的空间电荷层厚度随浸泡时间延长而有逐渐减小的趋势。添加纳米二氧化钛粉体,可促进RTV硅橡胶涂膜的导电行为由n型半导体导电特征转变为p型半导体导电特征,当所添加的纳米二氧化钛的质量分数w(TiO2)=2%时,RTV硅橡胶涂膜转变为绝缘态。
The purpose of the paper is to realize the mechanism of semiconducting transformation of RTV silicone rubber 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, a novel semiconducting behaviour of RTV silicone rubber coating was proposed,and the influence of nano TiO2 on the semiconducting conducting behaviour of RTV silicone rubber coating in the electrolyte was studied. The potential-capacitance method, combining with Mott- Schottky analysis, were utilized to study the influence of nano TiO2 on the conducting behaviour of RTV silicone rubber coating in 5 % Na2 SO4 solution. Results show that adding nano TiO2 in RTV silicone rubber coating decreases its Csc, and increases its thickness of space charge layer. With increasing immersion time, the thickness of space charge layer of nano composite RTV silicone rubber coating might decrease. Adding nano TiO2 in RTV silicone rubber coating could make the RTV silicone rubber coating to change from n-type to p-type semiconductor, then to an insulator while adding 2% nano TiO2.