Covalent functionalization can be achieved through various chemical reactions: 1. Oxidation: Introduction of oxygen-containing functional groups (e.g., hydroxyl, carboxyl) onto the surface of nanomaterials. 2. Cycloaddition Reactions: Reactions such as 1,3-dipolar cycloaddition to attach organic molecules to the nanomaterial surface. 3. Diazonium Chemistry: Involves the formation of diazonium salts which can react with nanomaterial surfaces to form covalent bonds. 4. Silane Coupling: Silane agents are used to form covalent bonds with hydroxyl groups on the surface of nanomaterials.
