Electrochemical study of ethanolic Lentinula Edodes extract as a “green” inhibitor for corrosion mitigation of low-carbon steel in sulfuric acid

The ethanolic extract of Lentinula Edodes, a fungal species, was evaluated as an ecological, green inhibitor to mitigate corrosion of carbon steel (CS) in acidic media. The Lentinula Edodes body fruit extract (LEBFE) was obtained using a well-established chemical method. Various electrochemical methods were employed to investigate the LEBFE’s corrosion inhibition efficiency under different operating conditions. The results showed that LEBFE is an effective mixed-type corrosion inhibitor, with a maximum corrosion protection efficiency 88.5 ± 0.2%. The inhibitor demonstrated efficient corrosion inhibition of the carbon steel surface over extended immersion periods and at various electrolyte temperatures. The FTIR and UV/Vis results indicated that the LEBFE extract contains compounds containing oxygen and nitrogen heteroatoms, which are known to interact strongly with carbon steel. The adsorption mechanism of the inhibitor on the carbon steel surface was based on physisorption, following the Langmuir isotherm. The results support the conclusion that LEFBE can be considered an effective and eco-friendly green inhibitor to control low-carbon steel corrosion in acid media.