A new approach for preparation of semi-transparent superhydrophobic coatings by ultrasonic spray hydrolysis of methyltrimethoxysilane

Abstract A novel nebulizing spray hydrolysis approach was used for preparation of semi-transparent superhydrophobic coatings. Methyltrimethoxysilane was dissolved in water:ethanol mixture and ultrasonically sprayed on different substrates. Superhydrophobic coatings with a contact angle (CA) as high as 164° and a sliding angle below 5° were obtained. FESEM and AFM revealed a hierarchical micro-nano binary structure with nanometric roughness of the coatings. The coated glass substrate exhibited transmittance close to 80%. The prepared coating showed great self-cleaning and water jet repellency behaviors. The superhydrophobicity of the samples was remained after subjecting to ambient conditions for 50 days. The coating was also durable under water flushing test.