Organic–inorganic hybridisation strategy for synthesizing durable colored superamphiphobic coatings

Abstract

Combining colored coatings with superamphiphobic coatings faces challenges such as low chromaticity, poor durability, and high cost. In this study, we report a simple, rapid, and mass-producible method for preparing colored superamphiphobic coatings based on an organic–inorganic hybridization strategy. We employed metakaolin, and nanosilica, combined with organic dyesand modified with fluorosilanes via physical milling, which was subsequently sprayed onto various substrates. By modulating the mass ratio of MK and SiO₂, the powders were milled to form a cauliflower-like micro/nanocluster structure, creating an air cushion at the solid–liquid interface. By combining this method with the chemical inertness of fluorosilanes, we achieved a substantial increase in coating durability. The coating maintained a high contact angle and low sliding angle after 48 hours of acid and alkali corrosion and UV irradiation. Additionally, it exhibited low adhesion and good self-cleaning and antifouling properties. Notably, the colored coating retained high color fastness to acidic and alkaline vapors and UV irradiation, demonstrating good durability. It maintained color and wettability after 150 days of outdoor exposure. This coating is available in a variety of colours, compatible with different substrates, suitable for large-scale production and has potential applications in heritage restoration and fresco painting.