Fabrication of BTA-MOF-TEOS-GO nanocomposite to endow coating systems with active inhibition and durable anticorrosion performances

Abstract A nanocomposite was fabricated with both excellent corrosion inhibitor encapsulating capacity and the ability of controlled delivery of benzotriazole (BTA) for simultaneously endowing coating systems with both active and passive anti-corrosion performances. The metal organic frameworks (MOFs) were synthesized and served as nanocontainers to load BTA. On this basis, tetraethyl orthosilicate (TEOS) was further added to form a film to wrap MOFs. The addition of TEOS endowed coatings with pH-responsive and active inhibition abilities, due to the film would break under acid or alkaline conditions. Moreover, the resultant compounds were further combined with graphene oxide (GO), cause GO had an superior barrier property and impermeability. On the other hand, there were abundant oxygen-containing functional groups on GO, which could be modified to improve the dispersion of GO in epoxy coatings. The fabricated nanocomposites were comprehensively characterized with Fourier Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric Analysis (TGA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Ultraviolet-visible spectroscopy (UV–vis) test was utilized to estimate the release behavior of BTA. Electrochemical Impedance Spectroscopy (EIS) was performed to characterize the corrosion behavior of various composite coatings. Results demonstrated that the BTA-MOF-TEOS-GO incorporated into the epoxy coatings showed the highest impedance values up to 8.6 × 108 Ω cm2, indicating the most excellent and durable anti-corrosion properties.