Nanoscale surface coatings based on plant phenolics

Surface coatings are integral to virtually all manufactured products and structures. The use of nanomaterials is currently making an extraordinary impact in the surface coatings field. In general, coatings and films play diverse roles such as improving product's appearance, increasing shelf-life by minimizing mechanical damage, weathering, and corrosion. The coatings render specific functionality or property to the product such as hydrophilicity, hydrophobicity, and insulation, etc. Recently, with the advancement in nanotechnology, various approaches are available to fabricate nanocomposite and nanostructured coatings for a wide range of applications. This has opened up exciting opportunities to improve the features of the surface coatings and their associated materials. Although the use of synthetic coating materials still dominates the field, there is an overwhelming surge to explore green, natural bio- and plant-based materials in recent years. This book chapter provides an overview of the nanoscale coatings based on phenolic compounds abundant in the plant kingdom and their role in designing functional adhesive coatings. The phenolic based adhesive films possess a broad range of applications in fields such as biomedicine, energy, and environment. First, we present a wide array of functional materials that can be engineered leveraging the universal adhesion properties of the phenolic building-blocks, such as metal-phenolic networks and polydopamine films. Next, the available coating methods are discussed along with their adhesion mechanisms. Finally, the applications of nanoscale coatings and functional materials derived from phenolic compounds are discussed, highlighting their uses in underwater adhesives, catalysis, energy), biomedical, and environmental remediation applications.