Mechanochemical Coupling of Alkylsilanes to Nanoparticles for Solvent-Free and Rapid Fabrication of Superhydrophobic Materials

Excellent repellencytoward water is one of the main characteristicsof superhydrophobic coatings that endow application potential in variousareas. However, the complex and time-consuming process involved inpreparing universally applicable superhydrophobic coatings, especiallythe step that involves modifying intrinsically hydrophilic inorganicoxide nanoparticles with hydrophobic alkylsilanes, limits their practicalapplications. This study demonstrates a rapid and eco-friendly approachto preparing superhydrophobic surfaces by chemically grafting alkylsilanemolecules onto silica nanoparticles using a mechanochemical process.The key advantages of this approach are (i) rapid process with preparationtimes that are orders of magnitude shorter than those of conventionalmethods, (ii) zero-solvent usage, and (iii) overcoming the need fortedious separation and drying steps. The resultant surface exhibitssuperhydrophobicity with a water contact angle of 172 & DEG; and asliding angle of 1 & DEG;. A monolith prepared by compressing the powderexhibits superhydrophobicity, durability, and antifouling abilityagainst urine. The superhydrophobic surface inhibits the growth oftwo of the most common pathogenic bacteria. The bacterial growth wasreduced by 10(7.07) for Escherichia coli and 10(5.78) for Staphylococcus aureus. The proposed approach is practical, swift, and cost-effective,making it a scalable and eco-friendly technique for the solvent-freepreparation of superhydrophobic surfaces.

Automated summary

This study presents a rapid and eco-friendly approach to preparing superhydrophobic surfaces by chemically grafting alkylsilane molecules onto silica nanoparticles using a mechanochemical process. The resulting surface exhibits high water contact angle, low sliding angle, durability, and antifouling ability against urine. The proposed approach is practical, swift, and cost-effective, making it a scalable and eco-friendly technique for the solvent-free preparation of superhydrophobic surfaces.