CONTACT ANGLE: The contact angle is the angle formed where a liquid meets a solid surface and is a key indicator of the surface’s wettability. A high contact angle (above 90°) signifies that the surface is hydrophobic, leading to water beading up. On the other hand, a low contact angle (below 90°) indicates a hydrophilic surface, causing water to spread out. Specifically, graphene coatings have a contact angle ranging from 110-118 degrees, while traditional ceramic coatings range between 100-110 degrees. This higher contact angle in graphene coatings demonstrates their superior hydrophobicity compared to traditional ceramic coatings.

SLIDE ANGLE: The slide angle determines the incline at which a water droplet begins to roll off a surface. For graphene coatings, this angle is between 5-15 degrees, while for traditional ceramic coatings, it’s between 20-30 degrees. A lower slide angle indicates a more hydrophobic surface, meaning water rolls off more easily. This suggests that graphene coatings exhibit higher hydrophobicity than traditional ceramic coatings. Such a property offers benefits like self-cleaning effects, reduced water spots, and enhanced protection. While the contact angle measures water “beading” on a surface, the slide angle assesses its ease of roll-off.