Corrosion inhibition of a novel antihistamine-based compound for mild steel in hydrochloric acid solution: experimental and computational studies.

Focused on the assessment of the diphenhydramine hydrochloride (DPH) capabilities as an alternative to conventional and harmful industrial corrosion inhibitors, electrochemical techniques were employed. The optimum concentration of 1000 ppm was determined by molecular simulation and validated through electrochemical experiments. The results acquired from the electrochemical impedance spectroscopy (EIS) study showed that DPH at a concentration of 1000 ppm has a corrosion efficiency of 91.43% after 6 h immersion. The DPH molecules' orientation on the surface was assessed based on EIS predicting horizontal adsorption on the surface. Molecular simulations were done to explore the adsorption mechanism of DPH. The DPH molecules' orientation on the surface was also assessed based on computational studies confirming the horizontal adsorption predicted by EIS.

Designing a non-hazardous nano-carrier based on graphene oxide@Polyaniline-Praseodymium (III) for fabrication of the Active/Passive anti-corrosion coating.

In this work, graphene oxide (GO) based nano-platforms were applied as a non-hazardous solid container with high encapsulating capacity and controllable release activity of eco-friendly inhibitor. For the first time, the adsorption and release properties of the praseodymium cations (Pr3+) on GO nanosheets functionalized with polyaniline (PANI) were investigated. The Pr3+ cations adsorption/desorption capacity of GOPANI nano-sheets was assessed by Inductively Coupled Plasma (ICP), X-ray photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FE-SEM), and High-resolution transmission electron microscopy (HR-TEM) techniques. The obtained results proved that the container modified with Pr3+ cations at pH of 7, 600 ppm of adsorpt, and 1 mg/cc of adsorbent dosage provided the highest capacity of inhibitors adsorption/release rates. The adsorption capacity of the GO-PANIs reached more than 500 mg/g. Also, the modified carrier desorbed about 70 % of loaded Pr3+ cations in the corrosion simulated condition. The self-healing anti-corrosion ability of the constructed containers in an organic-inorganic hybrid coating (OIHC) was shown by electrochemical analyses results. The resistance of coating with the loaded carriers has increased about 1 order of magnitude in comparison with the neat silane. Moreover, the scratched coatings containing the inhibitor loaded GO-PANIs showed extraordinary total resistance of about 25 Kohm. cm2.