LDH has been grown: What is next? Overview on methods of post-treatment of LDH conversion coatings

Current implementation of Industry 4.0, the fourth stage of industrialisation, implies application of novel approaches for manufacturing oriented on strong personalisation and customisation of products. In this context, formation of active multifunctional surfaces with on demand tailored properties can be considered as a keystone in the area of materials production. Nowadays, active multifunctional surfaces based on layered double hydroxides (LDH) are in the focus of numerous studies. Such interest is related to ability of LDH act as active "nanocontainers", i.e. to intercalate and release active species in controllable manner. Formation of LDH-based materials with diverse physical-chemical properties for various applications can be achieved through their adjustable post-treatment. This review presents the actual state-of-the-art of LDH post-treatments, including methods preserving the LDH structures such as modifications with polymers, hydrophobic molecules and intercalation of functional species into their galleries; as well as approaches resulting in host LDH layers rearrangement like thermal treatment and recrystallization of layered double hydroxides to metal organic frameworks (LDH-to-MOF).