Enhanced protective Zn–Al layered double hydroxide film fabricated on anodized 2198 aluminum alloy

•Zn–Al LDH films were fabricated on anodized 2198 aluminum alloy with ST.•The ST led to a compact layer structure and enhanced anticorrosion performance.•The intercalated VO3− anion in the LDH layer could be gradually released.•The inhibitor-containing film provided a significant long period of protection.

Zn–Al layered double hydroxide (LDH) film was prepared via an in␣situ growth method on anodized 2198 aluminum alloy. Then, inhibitor anions of vanadate were intercalated into the interlayer galleries of the LDH through anion exchange process. The structure, morphology, composition and corrosion resistance of the LDH films were investigated. The results showed that the sealing treatment of the anodic aluminum oxide layer greatly influenced the growth and crystallization of LDH crystals, which led to enhanced corrosion resistance. The vanadate loaded LDH exhibited a significant long period of protection for the filmed aluminum alloy substrate.