Ti3C2Tx MXene/MoS2 hybrid nanocomposites for synergistic smart corrosion protection of epoxy coatings

Abstract

MXene nanosheets have recently become a focus of research for corrosion protection due to their two-dimensional, sheet-like structure and distinct physicochemical characteristics. Nevertheless, their susceptibility to restacking and oxidation restricts their practical applications. To address this, the study proposes a custom hybrid structure by growing molybdenum disulfide (MoS₂) nanoparticles on the Ti₃C₂ MXene nanosheets (MX/MS) to prevent oxidation and restacking. This innovative structural design is essential for corrosion-protective coatings, as the sheet-like configuration enhances the barrier properties. The manufacturing of the MX/MS nanoparticles was verified by their characterization employing field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The barrier properties and self-healing functions of the nanoparticle-filled epoxy coatings were evaluated using electrochemical impedance spectroscopy (EIS) and salt spray tests. The epoxy resin including 0.5 wt% MX/MS nanoparticles exhibited outstanding corrosion resistance, with an impedance value (|Z|_0.01Hz) of 23.77 GΩ.cm² after 70 days of immersion. After 48 h of immersion, the coatings also showed a high impedance value (log|Z|_0.01Hz = 4.24) and excellent self-healing capabilities in the scratched areas. Additionally, after 42 days, the filled nanohybrid coatings showed the least amount of rust and corrosion product according to salt spray analysis. The results of cathodic delamination and pull-off tests indicated that in comparison to the neat epoxy (11 mm and 70 %), the filled coatings containing the synthesized nanofiller had the lowest cathodic delamination radius (1.7 mm) and lowest adhesion loss (46 %). This study highlights the effectiveness of Ti₃C₂/MoS₂ hybrid in enhancing the anticorrosive performance of organic coatings, offering a novel approach for designing high-performance additives with promising applications in various fields requiring corrosion protection.