ABSTRACT
A now-expired medication called isoprinosine was examined in NaOH (0.50 M) solutions as a potential novel inhibitor of aluminum corrosion. The inhibitory effectiveness of the isoprinosine compounds was examined utilizing different electrochemical tests (open circuit potential OCP, potentiodynamic polarization and electrochemical impedance spectroscopy EIS), surface examination and quantum calculations. Increases in isoprinosine concentration were seen to increase the inhibitory efficacy. It was discovered that the inhibitory action, which results in the inhibition of charge and mass transfer and protects the aluminum against harmful ions, was brought on by isoprinosine molecules adhering to the aluminum surface. Additionally, the surface morphology of Al dissolved in a 0.50 M NaOH solution without and with the existence of an isoprinosine molecule was analyzed using SEM/EDX and AFM techniques. Utilizing the optimized geometric parameters of the ground state molecules, FMO simulations and additional studies were executed successfully utilizing the density functional theory (DFT/B3LYP/6-311++G(d,p)). Based on the expected energies for the molecular carriers of charge, HOMO and LUMO. Calculations are also done for the AIM charges, Fukui functions, AIM charges, and excitation energies. Furthermore, molecular dynamic was simulated to explore the corrosion inhibition efficiency and mechanism of inhibition. The computational results are in the same agreement with experimental results, showing that isoprinosine can inhibit the corrosion of aluminum in 0.5 M NaOH.
ABSTRACT
Utilizing environmentally acceptable substances as inhibitors of metal corrosion is one of the most important strategies to reduce corrosion. In alkaline solutions (1.0 M KOH), the influence of albumin egg as a green corrosion inhibitor for copper was studied via a mix of experimental and theoretical investigations. Cyclic voltammetry (CV), open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), AFM, and SEM/EDX methods were all utilized to examine the inhibitory effect of albumin egg. By increasing the amount of albumin egg in the corrosive solution, the inhibition efficiency is increased. The albumin egg is a highly effective cathodic type inhibitor, according to electrochemical tests, with an inhibition efficiency of up to 94%. It also follows the Langmuir isotherm during adsorption. Investigations using SEM/EDX and AFM show that the albumin egg can create an adsorption layer on the surface enabling the shielding of the copper surface from harmful ions. In order to better understand the molecular structure of the albumin egg and its inhibitory action against corrosion, computational and molecular dynamics simulation techniques were also employed for calculating the electronic characteristics of inhibitor molecules. Calculations were made for total energy (TE), change in total energy (DET), energy gap (ΔE), ELUMO, EHOMO, dipole moment (D), and softness (δ). Utilizing the Monte Carlo simulation, the mechanism of albumin egg adsorption on the surface of Cu was investigated. The theoretical outcomes were found to confirm the empirical results.