LAUSR

A fundamental challenge in artificially structured or chemically modified superhydrophobic surfaces is their poor chemical, mechanical and structural robustness towards different mechanical abrasions. This limits their application potential in different fields of science and technology. Herein, a stable waterborne superhydrophobic material composed of clay particles is developed through a one-pot chemical modification in ambient conditions, forming durable micro-nano dual-structured coatings at room temperature over a range of substrates, without adhesive. This chemical modification inverts the inherent hydrophilic nature of clay particles and provides an excellent superhydrophobic surface having a water contact angle>170°(±2°) and contact angle hysteresis<5°(±2°). The coating shows excellent durability against various induced damages (mechano-chemicalenvironmental) and works efficiently both in air and within oils. The observed property is due to the controlled surface energy obtained by the incorporated chemical functionalities and enhanced surface roughness facilitated by the hydrophobic-effect during slow evaporation of 2 water from the coating material. Being a stable water-dispersion, it enables large area coatings, thereby minimising safety and environmental concerns. Use of this material to develop rugged waterproof-paper for various paper-based technologies is also demonstrated. As clay is commercially available and economical, we believe, this scalable organic-solvent-free superhydrophobic material will have a positive impact on various industries.