New approach using fluorescent nanosensors for filiform corrosion inhibition

•Development of smart composite coatings combining nanocontainers with fluorescent dye and inhibitor.•Detection by fluorescence of the initial stage of the degradation in FFC.•Inhibition of cathodic delamination during the FFC. Filiform corrosion (FFC) is a degradation affecting coated steel in atmospheric conditions. For industrial application the corrosion detection at the early stage is important to apply the reliable protection. Investigation on the use of nanocontainers for the detection and protection of organic layer is described. Fluorescent dye was used to detect the active corrosion and to evaluate the efficiency of inhibitors encapsulated inside PVB model organic coating. Active dissolution is located at the filament head whereas the cathodic reaction occurs along the tail where the oxygen concentration is higher. The fluorescent dye use is a relevant technique for the detection of corrosion early stages and inhibition efficiency.