CuO-based nanocomposite: synthesis, characterization, and evaluation of the corrosion inhibition effectiveness for mild steel in HCl

Mitigating mild steel (MS) deterioration within acidic environments is critical for minimizing economic losses. CuO nanoparticles/arginine/tyrosine (CAT) was synthesized by modifying CuO nanoparticles with a 10.0 % solution of each arginine and tyrosine, through the use of ultrasonication. The characterization of CAT was conducted utilizing X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, transmission electron microscopy and Brunauer-Emmett-Teller analysis. To investigate MS corrosion in 1.0 M HCl, both potentio­dynamic polarization and electrochemical impedance spectroscopy techniques were employed. The XRD results indicated the presence of distinct peaks, confirming the crystalline structure of CAT, with an average crystallite size equal to 39.5 nm. The FTIR band observed within the range of 580-610 cm-1 is likely attributable to Cu-O stretching vibrations. TEM imaging demonstrated that CAT comprises spherical and well-dispersed particles. Furthermore, the surface area of CAT was determined to be 221 m² g-1, with a pore diameter of 2.137 nm, indicating its mesoporous nature. The variation in corrosion potential was below 85 mV, indicating that CAT functioned as a mixed-type inhibitor. The charge transfer resistance rose from 7.3 W cm2 without CAT to 226.8 W cm2 at 1000 ppm of CAT, demonstrating the potential of CAT as an inhibitor for MS corrosion in HCl. CuO, arginine, and tyrosine exhibit HOMO and LUMO properties that could play a significant role in corrosion inhibition.