Kumari, D.Venugopal, P.P.Reena Kumari, P.D.Chakraborty, D.2026-02-042022Journal of Adhesion Science and Technology, 2022, 36, 18, pp. 2020-20451694243https://doi.org/10.1080/01694243.2021.1999703https://idr.nitk.ac.in/handle/123456789/22862Quercetin was evaluated as corrosion inhibitor for AA6063 in 0.5 M HCl solution by employing weight-loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX), Atomic Force Microscopy (AFM), X-Ray photoelectron spectroscopy (XPS) techniques allied to quantum chemical studies. Electrochemical results substantiate that the inhibition efficacy of quercetin increases proportionally with the concentration of the inhibitor. The effect of temperature on the corrosion behavior of the alloy was studied in the range of 30–60 °C. Potentiodynamic polarization study confirms the mixed type of inhibition by quercetin with preferential control of the cathodic reaction. The adsorption of quercetin on alloy surface was explained through the Langmuir adsorption isotherm model. ΔG°<inf>ads</inf> values and its variation with the temperature ensured spontaneous adsorption through chemisorption and the process was endothermic. Further, quantum chemical parameters calculated from Density Functional Theory (DFT) method for quercetin, proved a perfect correlation between structure and corrosion inhibition efficiency. © 2021 Informa UK Limited, trading as Taylor & Francis Group.AdsorptionAluminum alloysAluminum corrosionChemical analysisChlorine compoundsCorrosion inhibitorsCorrosive effectsElectrochemical corrosionElectrochemical impedance spectroscopyEnergy dispersive X ray analysisFlavonoidsHydrochloric acidPhenolsPolarizationPotentiodynamic polarizationQuantum chemistryScanning electron microscopyX ray diffraction analysisX ray photoelectron spectroscopyAcid inhibitionAluminum alloy 6063Corrosion inhibitionDensity functional theoryDensity-functional-theoryElectrochemical methodHCl solutionHydrochloric acid solutionQuercetinTheoretical study