Multifunctional Superhydrophobic Composite Coatings with Remarkable Passive Heat Dissipation and Anticorrosion Properties

Effective surface passive heat dissipation and durable superhydrophobicity are highly desired for promoting more flexible applications of power-intensive energy systems of aluminum and aluminum-based composites. Herein, we developed a simple and universal approach to fabricate durable superhydrophobic composite coatings composed of hexamethyldisilazane-modified silicon carbide nanowires (HMDS-SiCNWs) and fluorosilicone (FSi) resin. The as-prepared superhydrophobic coating on aluminum substrates exhibited excellent water-repellent property, stain repellency, corrosion resistance, and outstanding mechanical durability, largely due to the hierarchical micro-/nanoscale structure and low surface energy created by HMDS-SiCNWs on the FSi resin matrix. The coatings maintained superhydrophobic after exposure to harsh conditions such as knife scraping, tape peeling, and immersing in boiled water and liquid nitrogen for 1 h. When functioned on an Al radiator for a constant 18 W heat source, such a coating can decrease the temperature by as much as 10 degrees C and improve the cooling efficiency by up to 10%. Therefore, the combined passive heat dissipation and superhydrophobic multifunctional coating shows promising application in heat exchange systems which are required to be exposed to harsh external environments.