Simultaneous Optimization of the Surface Hydrophobicity and Surface Charge Distribution of Insulating Materials

Abstract Superhydrophobic materials have great application potential in the insulation equipment of power systems because their excellent water‐repelling and self‐cleaning abilities maintain clean and dry surfaces. However, the electrical performance of superhydrophobic materials has been ignored for a long time; surface charge accumulation is a significant problem when they are used in direct‐current power systems. A scheme that concurrently optimizes the surface hydrophobic and electrical characteristics of insulating materials is urgently needed. Herein, a simple method for designing superhydrophobic coatings using zinc oxide and polydimethylsiloxane is proposed. Silicone rubber is chosen as the experimental material because of its wide application in insulators. Contact angles greater than 160° and sliding angles smaller than 2° are achieved. In addition, the coating exhibits excellent optimization of the surface charge distribution. Compared with pristine silicone rubber, the coated silicone rubber has a more uniform charge distribution, lower initial charge accumulation, and faster charge dissipation. The trap parameters and conductivity are used to explain the mechanism responsible for this phenomenon. The combination of superhydrophobicity and surface charge optimization can provide new insights for improving the performance of insulation materials in power systems.