Self-assembly of coumarin molecules on plasma electrolyzed layer for optimizing the electrochemical performance of AZ31 Mg alloy

Kaseem M., Dikici B., Dafali A., Fattah-Alhosseini A.

Journal of Magnesium and Alloys, cilt.11, sa.5, ss.1618-1628, 2023 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 11 Sayı: 5
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1016/j.jma.2022.10.011
  • Dergi Adı: Journal of Magnesium and Alloys
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1618-1628
  • Anahtar Kelimeler: Corrosion, Coumarin, DFT, Hybrid coating, Mg alloy, Porous layer
  • Atatürk Üniversitesi Adresli: Evet

Özet

A novel inorganic-organic layer with outstanding corrosion resistance in a 3.5wt.% NaCl solution was fabricated by taking advantage of the unique interactions between coumarin (COM) molecules and the porous layer formed on Mg alloy. To achieve this aim, the AZ31 Mg alloy coated via microarc oxidation (MAO) coating was placed in an ethanolic solution of COM for 6 and 12 h at 25 °C. By reducing the surface area exposed to the corrosive species, the donor-acceptor complexes produced by the particular interactions between the COM and MAO surface would successfully prevent the corrosion of Mg alloy substrate. The MAO layer would provide the ideal sites for the charge-transfer-induced physical and chemical locking, leading to uneven organic layer nucleation and crystal growth with a thatch-like structure. To evaluate the formation mechanism of such hybrid composites and highlight the key bonding modes between the COM and MAO, theoretical simulations were conducted.