Bioinspired MXene nanosheets with a trabecular void structure between epoxy layers for enhancing corrosion and impact resistance of composite coatings

• The directional arrangement of MXene nanosheets was achieved to maximise the physical barrier effect of nanosheets. • A trabecular-trabecular void structure was constructed to provide the composite coating with excellent impact resistance. • Tannic acid imparts robust interfacial compatibility to the nanosheets and enhanced long-term service properties of coatings. Polymer coatings are susceptible to corrosion and cracking when exposed to seawater conditions, limiting their effectiveness in the field of protection. Inspired by the structure of trabeculae on the sheath wings of beetles, Ti 3 C 2 MXene@TA two-dimensional nanofillers with a trabecular-trabecular void structure were prepared by tannic acid (TA) bonding. Employing a spraying process, directional arrangement of nanosheets was achieved, leading to the fabrication of biomimetic composite coatings. The presence of directionally arranged MXene nanosheets endowed coatings with durable barrier properties to prevent rapid invasion of corrosive media. Moreover, the presence of TA improved the interfacial compatibility between nanosheets and epoxy resin, thereby improving the dispersion properties of nanofillers to maximize physical barrier properties. The trabecular structure imparted by TA enhances the impact resistance of composite coatings. In addition, the trabecular-trabecular void structure provides stress transfer and energy absorption, thus enhancing mechanical properties of the coating (compression modulus, energy absorption, etc.). Therefore, Ti 3 C 2 MXene@TA nanocomposite coatings featuring a trabecular-trabecular void structure show considerable promise for severe marine corrosion applications.