Novel Synthesis, Characterization, and Corrosion Inhibition Properties of Nanodiamond−Polyaniline Films

Functional and composite nanodiamonds (NDs) are rapidly emerging as promising materials for the next generation for quantum information processing, electronic material, magnetotometry, novel imaging, and IR fluorescence applications, etc. Nanocomposites of ND particles with conductive polymers [i.e., polyaniline (PANI)] displayed novel properties resulting from the molecular level interaction of diamond with PANI molecules. We have synthesized for the first time the ND-PANI nanocomposites by oxidative polymerization of aniline using ammonium peroxydisulfate [(NH4)2S2O8)] under controlled conditions. The ND-PANI nanocomposite films were characterized by UV−vis, FTIR, electrochemistry, impedance, scanning electron microscope, transmission electron microscope, and electrical conductivity techniques. Current−voltage characteristics of ND-PANI nanocomposite show the ohmic junction. The electrochemical investigation on ND-PANI revealed the wider potential values with independent redox characteristics of PANI and ND. There is an interaction of the free electron pairs of the nitrogen atoms of the PANI with a charged molecule on the surface of ND with PANI. The concept of using an active electronic barrier ND-PANI barrier built-in electric field is created at the metal surface. The ND-PANI takes advantage of the excellent corrosion inhibitor characteristics of steel and aluminum due to its chain conformation and electronic properties, as demonstrated in this work.