Achieving parallelly-arranged Ti3C2Tx in epoxy coating for anti-corrosive/wear high-efficiency protection

Two-dimensional Ti3C2Tx has demonstrated great potential for enhancing the protection performance of epoxy coating, but randomly-arranged Ti3C2Tx fails to meet higher expectations on the anti-corrosion/wear under extreme conditions. Here, the positively-charged Ti3C2Tx (f+-Ti3C2Tx) flakes obtained by functionalization and protonation were directionally distributed in the epoxy coating using an electrophoretic deposition method. The migration/rotation of f+-Ti3C2Tx flakes under electric field force and their mutual repulsion are responsible for the parallel alignment with the horizontal direction of coating. In particular, the epoxy coating incorporated with 1 wt % f+-Ti3C2Tx exhibits a near-perfect internal arrangement structure. When exposed to saline solution for the long period, its water absorption is decreased by 85.33% and the lowest-frequency impedance is increased by four orders of magnitude compared with randomly-arranged Ti3C2Tx hybrid epoxy coating, because parallelly-arranged f+-Ti3C2Tx with orientation factor can maximize the internal tortuosity and optimize the barrier properties of epoxy coating against aggressive ions. Furthermore, a significant friction reduction and an order of magnitude reduction in wear rate are obtained, mainly based on the increase of the deflection and branching of cracks in the friction process thus decreasing the probability of coating exfoliation. Therefore, the directional alignment of Ti3C2Tx in the epoxy coating can immediately upraise the protection properties’ ceiling, specifically suitable for long-term anti-corrosion/wear applications.