Superhydrophobic sol-gel nanocomposite coatings with enhanced hardness

► Hard superhydrophobic sol-gel composite coatings were fabricated using a sol of Methyltriethoxysilane and colloidal silica. ► They had a highly porous structure with nano size voids and micron size bumps. ► They exhibited very good hardness and adhesion strength with the substrate. ► Superhydrophobicity in these coatings is a combined effect of surface roughness and low surface energy due to siloxane bond network formation.