Adsorption of cobalt (II) 5,10,15,20-tetrakis(2-aminophenyl)-porphyrin onto copper substrates: Characterization and impedance studies for corrosion inhibition

► Deposition of cobalt (II) 5,10,15,20-tetrakis(2-aminophenyl)-porphyrin on copper. ► Uniformly and homogeneously distributed film. ► Open circuit potential of the modified copper electrode becomes more positive. ► Corrosion current density decreases by a magnitude of 10 times. ► Charge-transfer resistance reaches an inhibition efficiency of 97%.