Engineering multifunctional polymeric composite coatings based on BP@ZIF-67 for superior corrosion/wear resistance and flame retardancy

In this study, BP@ZIF-67 (BZ), a special heterostructural nanofiller, was innovatively constructed by growing ZIF-67 in situ on black phosphorus (BP) nanosheets, and introduced it into the waterborne epoxy resin (WEP) coating. In addition, only 0.4 wt.% BZ nanofiller needs to be introduced to give the WEP coating an excellent overall performance improvement. After 42-day of immersion in 3.5 wt.% NaCl solution, the impedance modulus of 4-BZ/WEP in the low frequency region of 0.01 Hz (|Z_{0.01 Hz}|) jumped two orders of magnitude compared to the pure WEP coating, showing a strong corrosion protection barrier effect; The wear rate of the 4-BZ/WEP coating is greatly reduced by 89.98% compared to the blank WEP coating, and the wear resistance has been qualitatively improved. And compare with the blank WEP coating, the peak heat release rate (PHRR) of the 4-BZ/WEP coating is reduced by 10.22%, effectively improving the fire safety and thermal stability of the material. The strategy of using BP nanosheets and ZIF-67 to construct multifunctional nanofillers provides a promising new way for the development of high-performance waterborne epoxy composite coatings that integrate long-term corrosion protection, high wear resistance and good flame retardancy.