From molecular adsorption to interfacial barrier architecture: Sugarcane peel -derived inhibitor for corrosion of cold rolled steel

Sugarcane peel, an abundant agricultural by-product, is proposed as a renewable inhibitor in this study, demonstrating great potential for sustainable anti-corrosion strategies. The anti-corrosion capacity and mechanism of sugarcane peel extract (SPE) on the cold rolled steel (CRS) corrosion in 1.0 M HCl electrolyte were evaluated with gravimetric, electrochemical techniques, surface evaluations and theoretical simulations. The outcomes reveal that SPE strongly mitigates CRS corrosion from aggressive HCl solution, attaining an inhibition efficiency ( η w ) up to 91.2%. SPE adsorbs onto CRS in an exothermic process and follows the Langmuir model. SPE functions as a hybrid-type inhibitor, establishing a dense layer on CRS, and the corrosion mechanism unchanged. SPE effectively suppresses the interfacial charge transfer process and significantly blocks the CRS corrosion. Surface morphology and wettability investigations further confirmed the creation of barrier on CRS with the addition of SPE. Theoretical calculations indicate that the major active ingredients in SPE such as chlorogenic acid, p-hydroxycinnamic acid, and xanthohumol gather onto CRS through the active sites of aromatic rings and the heterocyclic compound. These molecules interact with CRS through the donor-acceptor mechanism, resulting in the development of barrier that impedes the erosive ions diffusion and enhances the corrosion resistant ability. This work underscores the promise of sugarcane peel extract as a sustainable corrosion inhibitor and offers both theoretical support and practical insights into applications of high-value agricultural waste. • SPE inhibits cathodic and anodic reactions with η w exceeding 90% on CRS in 1.0 M HCl. • SPE adsorption follows Langmuir model, reducing corrosion and boosting hydrophobicity. • Fe – N and Fe – S bonds show strong interfacial interaction between SPE and CRS. • Key SPE components, chlorogenic acid and xanthohumol, strongly bind to Fe (110). • The SPE layer isolates H⁺/Cl⁻ ions, producing low-mobility protective films.