Organic–InorganicComposite Strategy for FluorinatedWaterborne Polyurethane (WPU)@ZIF-8/Ti₃C₂T_<i>x</i> Coatings to Achieve Superior AnticorrosionProperties for Bronze Protection

The corrosion of ancient bronze relics and protection measures after excavation are of great importance to the study of historical and cultural heritage. At present, the bionic superhydrophobic surface anticorrosive coating is one of the main anticorrosive measures of bronze cultural relics. It aims to construct a barrier to prevent the contact between corrosive media and bronze to reduce the invasion of corrosive media. However, due to structural defects such as micropores in a single organic coating, corrosive media (O₂, Cl^–, and H₂O) can penetrate the coating to the metal matrix. Nanomaterials such as MXenes and metal–organic frameworks (MOFs) can fill structural defects such as microholes and microcracks of the coating, thereby improving the density of the coating. Therefore, to improve the performance of organic waterborne polyurethane (WPU) coatings with good chemical protection, nanomaterial ZIF-8/Ti₃C₂T_<i>x</i> was introduced based on the organic–inorganic hybrid theory. Finally, the coating was modified by 1<i>H</i>,1<i>H</i>,2<i>H</i>,2<i>H</i>-perfluorodecyltriethoxysilane, and the organic–inorganic composite coating was prepared. Characterizations of the composite coating were performed via Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller method, field-emission scanning electron microscopy/energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. Colorimetric measurements and reversibility experiments of the coating were also evidenced. According to the electrochemical impedance spectroscopy assessments, the |<i>Z</i>|_{0.01 Hz} value of the F-WPU@ZIF-8/Ti₃C₂T_<i>x</i> composite coating in a 3.5 wt % NaCl solution, which was higher compared to other composite coatings. Moreover, the <i>i</i>_corr value of the F-WPU@ZIF-8/Ti₃C₂T_<i>x</i> (3.344 × 10^–6 A cm^–2) composite coating is reduced by 2 orders of magnitude compared with F-WPU@ZIF-8 and F-WPU@Ti₃C₂T_<i>x</i> coatings. As a result, this organic–inorganic F-WPU@ZIF-8/Ti₃C₂T_x composite coating has good anticorrosion properties to bronze without causing an obvious color difference change and has potential application prospects in various metal material fields.