Mechanical durable ceria superhydrophobic coating fabricated by simple hot-press sintering

Abstract

Mechanical durability is always a significant challenge in the application and research of superhydrophobic surfaces. In this work, a mechanical durable ceria (CeO2) superhydrophobic surface was fabricated by a facile hot press sintering process of CeO2 powders on the Cu substrate. Combustion synthesis is firstly adopted to fabricate CeO2 powders because powders with suitable micro-roughness for superhydrophobicity could be obtained by this method. In order to achieve hierarchical microstructures, stainless steel mesh is used to be the template in the hot press sintering process. After 90-day storage in air, the surfaces maintain superhydrophobic performance, indicating that the coating exhibits good long-term durability. The as-obtained superhydrophobic surface shows excellent mechanical stability after ultrasonic treatments of 120 min. The morphologies of the coatings before and after ultrasonic are observed. It is found that the microstructure is stable enough to resist severe mechanical damage, indicating the strong binding force between superhydrophobic coating and the substrate. This hot-press method has also been used to prepare superhydrophobic CeO2 surfaces on other different metal substrates, which shows broad application prospects.