Superhydrophobic perpendicular nanopin film by the bottom-up process

We first fabricated the superhydrophobic film with a water contact angle of 178° based on a perpendicular nanopin fractal structure by a bottom-up process. Until now, only materials with an original water contact angle larger than 90°, which is classified as hydrophobicity, could be used to fabricate the superhydrophobic film (>170°) according to the possible fractal structure by a top-down process. Now, in this work, a water contact angle of about 178° can be achieved using a lauric acid-coated film with an original contact angle of 75°, which is classified as hydrophilicity, based on an ideal fractal structure for the superhydrophobic surface which is fabricated by the nanosize pin with 6.5 nm diameter.