Metallic coated substrates

A metallic substrate, wherein the surface of the substrate is coated with a coating layer comprising a metal having dispersed in the coating layer a plurality of sealed nanotubes loaded with an anti-corrosion agent wherein said anti-corrosion agent is (1) BTA or a BTA derivative, wherein said BTA derivative is selected from the group consisting of 4-methyl-1H-benzotriazole, S-methyl-1H-benzotriazole, 6-methyl-1H-benzotriazole and 5,6-dimethyl-1H-benzotriazole, 1-(2-pyrrolecarbonyl)benzotriazole (PBTA) and 1 (2-thienylcarbonyl)benzotriazole (TBTA), 1-hydroxymethyl benzotriazole and N,N-dibenzotriazol-1-ylmethylamine;

• and
• (ii) a phosphate salt;
• wherein said nanotubes are sealed with a material comprising metal ions, wherein said metal ions are ions of a transition metal or an alkaline earth metal;
• and
• wherein the phosphate salt comprises a polymeric oxyanion formed from three or more tetrahedral PO4 (phosphate) structural units linked together by sharing oxygen atoms.