LAUSR

Abstract Surfaces with fluid repellency are of great interest for a plethora of applications and introduction of the concept of wettability contrast has further expanded their application domain. Myriad of fabrication techniques are known to prepare superhydrophobic surfaces, however, for generating wettability contrast on a substrate comparatively very few methods are available. A preponderance of these methods involves intricate procedures and sophisticated instrumentation, making them not suitable for up-scaling. In this report, we have used a facile, eco-friendly and solvent-less egg-based approach for fabricating copper surfaces with wettability contrast. This multifaceted method is successfully utilized to design substrates suitable for different applications such as drop manipulation, directional fluid transport, and fog harvesting.