UV Light Triggered Fluorescence Coatings for Early-Stage Corrosion Detection in AA2024-T3 Based on V-CeO2 Nanocomplex

Abstract

Fluorescent corrosion indicators offer a promising avenue for identifying underlying corrosion on metallic substrates by sensing metal ions generated through corrosion reactions. A key component of fluorescence corrosion detection systems involves nanoparticles loaded with inhibitors. However, developing efficient fluorescent coatings has been hindered by challenges such as fluorescence quenching, sluggish response rates, side reactions, and the requirement for expensive instrumentation. To address these challenges, we present a novel approach involving synthesizing vanadium and cerium dioxide (V-CeO2) nanocomplex consisting of VOx NRs with ∼250 nm in length and ∼60 nm width and CeO2 NSs with a diameter of ∼80 nm were synthesized via modified solvothermal route, resulting in enhanced fluorescence efficiency, and reduced bandgap (1.94 eV) with photoabsorption in the UV range (365 nm). Simulated calculations (density of states (DOS) and integrated crystal orbital Hamilton population (ICOHP)) confirm the reduced bandgap, which facilitates the fast excitation of the electron, resulting in a quick response in fluorescence detection. The V-CeO2 nanocomplex with acrylic latex (Ac2403) as well as epoxy coatings, has been employed to fabricate fluorescent coatings on the AA2024-T3 substrate for early-stage corrosion detection. Both acrylic and epoxy coatings without color pigment(V-CeO2/Ac2403 and V-CeO2/epoxy) and with color pigments (V-CeO2/MO/Ac2403 and V-CeO2/SY/epoxy) show the excellent bright blue fluorescence by reacting with metal ions resulting from corrosion, forming a complex with Al3+ ions. Our findings demonstrate that the current fluorescent corrosion-detecting coatings provide a practical alternative to traditional coatings for real-time monitoring and meeting the increasing demands in potential applications.