Designing novel organic inhibitor loaded MgAl-LDHs nanocontainer for enhanced corrosion resistance

[Display omitted] •A high-efficiency approach of intercalating 5- aminoindazole (AIA) into the MgAl-LDHs was demonstrated.•The synthesized MgAl-AIA− LDHs displayed a controlled release behavior and excellent anti-corrosion performance.•Theoretical calculations provide favorable support for experimental results. The combination of LDHs nanocontainer and organic inhibitor demonstrates a great prospect in the field of corrosion protection. Whereas the traditional ion exchange method has a low efficiency owing to the small space and the firm force between the LDHs laminates. A high-efficiency approach of intercalating organic inhibitor into the LDHs is delivered in this work. The MgAl-LDHs loaded with 5-aminoindazole (AIA) were synthesized by separating the layered structures of hydrotalcites into single-layer nanosheets and then restructuring the exfoliated nanosheets with organic inhibitor. The as-synthesized LDHs-AIA− displayed a controlled release behavior and excellent anti-corrosion performance on the copper in 3.5 wt% NaCl solution, which were characterized by UV–vis spectra and electrochemical tests. Furthermore, a series of structure and morphology tests involving SEM, TEM, XRD, FTIR, XPS and TGA were also used for further analysis the LDHs. And the analysis of corrosion products and the anti-corrosion mechanism were carried out by SEM, XRD tests. The theoretical calculations concerning the adsorption of corrosion inhibitors on the copper surface were also investigated. It can be concluded that the inhibitor-loaded LDHs have the ability to adjustably release the corrosion inhibitor in corrosive medium, thereafter the corrosion inhibitor can adsorb onto the active sites of copper surface to prevent corrosion.