Formation of superhydrophobic surfaces

A surface comprising:

• a nanotexture formed by pillars in a substrate, where each pillar has a top, a base, a pillar center, and a base width of about 5 nm to about 100 nm, and wherein the pillars are patterned in an array with distances of about 5 nm to about 100 nm between adjacent pillar centers;
• and
• a hydrophobic coating on the pillars and on the substrate between the pillars such that the surface is superhydrophobic;
• wherein the pillars comprise nanostructures, the nanostructures exhibiting a water contact angle exceeding 160 degrees and a contact angle hysteresis smaller than 10 degrees;
• wherein the nanostructures comprise an hourglass shape;
• and
• wherein the top of each pillar, the base of each pillar, and the pillar center of each pillar are defined in the substrate such that an entirety of the hourglass shape is defined in the substrate.

A surface comprising:

• a nanotextured substrate comprising nanostructures, each nanostructure having a top, a base, a center, and a base width of about 5 nm to about 100 nm, wherein the nanostructures are arranged in a pattern having distances of about 5 nm to about 100 nm between adjacent centers;
• and
• a hydrophobic coating on the nanostructures and on the nanotextured substrate between the nanostructures such that the surface is superhydrophobic;
• wherein the nanostructures exhibit a water contact angle exceeding 160 degrees and a contact angle hysteresis smaller than 10 degrees;
• wherein the nanostructures comprise an hourglass shape;
• and
• wherein the top of each nanostructure, the base of each nanostructure, and the center of each nanostructure are defined in the nanotextured substrate such that an entirety of the hourglass is defined in the nanotextured substrate.