Double-doped LDH films on aluminum alloys for active protection

A double-doped layered double hydroxide (LDH) container film with cerium and vanadate ions was prepared in a two-step process. The Ce-doped ZnAl-LDH film was fabricated on aluminum alloy via a facile in situ growth method with urea hydrolysis, and then intercalated with V2O74− anions by anion-exchange process. The structure, morphology and composition of the as-prepared LDH films were investigated. A uniform and compact thin film was formed. EIS showed that the double incorporation of Ce(III) and V2O74− anions significantly enhance the impedance of the LDH film, indicating an effective protection for aluminum alloy by the active film.