Synthesis of a superhydrophobic self-cleaning coating through dual-scale carbon sphere based colloidal assembly

Superhydrophobicity can be seen in nature with varying degrees of wetting. The leaves of the lotus plant have long been identified for their superhydrophobic properties. Superhydrophobic surfaces have contact angles larger than 150° and their sliding angles are less than 10°. Herein we describe how, with the use of evaporated metals, the hydrophobicity of carbon spheres which are intrinsically hydrophobic can be altered to biomimic different states of wetting as seen in nature to create a superhydrophobic self-cleaning coating. Superhydrophobicity was displayed through the determination of contact angle and contact angle hysteresis. Dual-scale roughness was utilised to create the superhydrophobic coating with surface structure playing a vital role in its creation.