HYDROPHOBICITY OF RARE-EARTH OXIDE CERAMICS AND THEIR TECHNOLOGICAL IMPACT

摘要

Robust hydrophobic materials can have broad applications in various industries including energy, water, and transportation. Existing durable materials such as metals and ceramics are generally hydrophilic and require polymeric modifiers to render them hydrophobic, but these modifiers deteriorate in harsh environments. Therefore, robust hydrophobic surfaces have been difficult to realize and their widespread applicability has been limited. Here we demonstrate that all rare-earth oxide ceramics, ranging from ceria to lutetia, are intrinsically hydrophobic. We attribute this behavior to their unique electronic structure that minimizes polar interactions with interfacial water molecules. To demonstrate their technological potential, we show dropwise condensation, water repellency, and sustained hydrophobicity after exposure to high temperature, steam, and abrasive wear. Since these ceramics are intrinsically hydrophobic, they can preserve their hydrophobicity even after damage at the surface. Hence, we envision that this class of robust hydrophobic materials will have far-reaching technological potential in various industrial applications.