Creation of an Icephobic Coating using Graphite Powder and PTFE Nanoparticles

Ice accretion can cause numerous inefficiencies, structural stresses, and failures in applications ranging from building design to power generation and aerospace applications. Currently, some of the leading de-icing technologies, such as the ICE-WIPS system, utilize a heating element coupled with a superhydrophobic surface. The high power consumption inherent in these systems can make them expensive and impractical, especially when coupled with power generating systems. Reduced power consumption in these de-icing technologies can be achieved through increased absorption of solar radiation in the visible range while maintaining hydrophobic performance of a coating. In this work, a Polytetrafluorethylene (PTFE) and graphite-based superhydrophobic surface is proposed, which maintains similar hydrophobic performance to standard superhydrophobic surfaces. The novel coating demonstrates contact angles of upwards of 130^o and sliding angles of less than 4^o, while increasing solar radiation absorption in the visible range by approximately 139% over PTFE-based hydrophobic coatings. Icing wind tunnel tests where the coatings were exposed to visible light in order to simulate solar radiation were performed in a variety of different conditions in order to verify the improved de-icing capabilities introduced by the added graphite. The melting time per unit ice mass was reduced by upwards of 50% for glaze ice and 8.0% for rime ice over a comparable de-icing coating without added graphite. There was also a qualitative difference in de-icing performance, as the coating with added graphite demonstrated removal of ice in a single sheet from the base layer, in contrast to the PTFE only coating, which allowed for the ice to melt in multiple pieces from the model.