From the EIS results, the order of the protective efficiency of the PANI pigment is the following: PANI–BS (0.5%) ∼ PANI–LS2 (3%) > PANI–LS2 (1.5%) ∼ PANI–LS1 (3%) > PANI–BS (1.5%) ∼ PANI– LS1 (1.5%) > PANI–LS1 (0.5%) ∼ PANI–LS2 (0.5%) > PANI–BS (3%).