Enhancement of anticorrosion protection via inhibitor-loaded ZnAlCe-LDH nanocontainers embedded in sol-gel coatings

Inhibitor-loaded ZnAlCe layered double hydroxide (LDH) nanocontainers were prepared through the co-precipitation method. Vanadate and molybdate were used as guest inhibitors intercalating in the interlayer galleries of ZnAlCe-LDHs. The samples were characterized in terms of morphology, structure, and release behavior by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma (ICP) techniques. To investigate inhibition behavior, the LDHs particles were embedded in a hybrid sol-gel (SiO (x) /ZrO (x) ) layer on aluminum alloy 2024 measured by electrochemical impedance spectroscopy (EIS). The EIS results show that the sol-gel coating with inhibitor-loaded ZnAlCe-LDH particles exhibits high corrosion resistance due to the active inhibition by the dissolution of ZnAlCe-LDHs and inhibitor anions and the exchange behavior of LDHs. Compared with the addition of ZnAlCe-MoO4-LDHs, the coating embedded with ZnAlCe-V2O7-LDHs exhibited better anticorrosion abilities and provided effective protection after a long immersion time.