Experimental and theoretical assessments of the chamomile flower extract as a green corrosion inhibitor for aluminum in artificial seawater

Abstract

The anticorrosive qualities of a number of natural items have been researched because of the growing concern regarding the environmental contamination produced by conventional corrosion inhibitors. Through electrochemical measurements, the current study evaluated the effectiveness of chamomile flower extract (CFE) in preventing the corrosion of aluminum in an artificial seawater solution. Atomic force microscopy (AFM) and scanning electronic microscopy (SEM) were used for surface examination. Utilizing FTIR, the chemical composition of CFE extract was investigated. Density functional theory (DFT) computations were used to conduct theoretical analyses of its main constituents. According to the electrochemical tests, corrosion inhibition increased as inhibitor concentration increased and reached a moderate inhibition efficiency of 75.66% at 20 mL/L. Polarization curves showed that CFE molecules behaved as mixed-type inhibitors and that their adsorption process primarily followed the Freundlich isotherm. Examination of the corroded aluminum surface by SEM and AFM confirmed the adsorption of compounds present in the extract. The main constituents of the natural extract's electronic characteristics were determined using chemical quantum calculations, which also clarified interactions between inhibitors and metal surfaces as well as adsorption modalities.