The Preparation of a Colorful Aluminum Flake Powder with Smart Anticorrosion Properties by Encapsulation of Composited Metal–Organic Framework-Derived Layers

In this study, a novel strategy is utilized to prepare colored aluminum pigments with smart and optimal alkali resistance by in situ growth of multilayer composite nanomaterials on aluminum powders. A layer of a metal–organic framework (MOF) is constructed on the aluminum pigments by an in situ electrostatic self-assembly process. Copper-based metal–organic frameworks (CuMOFs) with excellent adsorption properties are utilized as nanocontainers for loading corrosion inhibitors (benzotriazole). The aluminum powder with the CuMOF functional layer (Al@CuMOF) has smart anticorrosion performance and vibrant colors. The MOF functional layer evenly releases benzotriazole to protect the aluminum powders from corrosive environments. Furthermore, the poly(trifluoroethyl methacrylate) layer with uniformity and denseness is tightly coated on the MOF functional layer to increase weatherability. The electrochemical impedance spectroscopy demonstrated that the highest impedance of the multifunction aluminum powders was as high as 7.23 × 105 Ω cm2, indicating excellent and durable chemical stability.