Investigation on the working mechanisms of sustainable corrosion inhibitors for mild steel in acid solutions: a review based on experimental and computational analysis

Corrosion of metals in diverse media degrades their functional and operational properties. After corrosion, metals are not as useful as they are in pristine conditions. Mild steel (MS) is a highly exploited metal in engineering works due to its supreme properties. Several methods have been adopted by the scientists to prevent the corrosion of MS; however, the prevention by natural products as corrosion inhibitors is more appreciated and needed due to environmental concerns. However, it is very important to know the inhibition mechanism of inhibitors before using them in prevention applications, especially in acids. This review gives a brief review of corrosion inhibitors and focuses on their working mechanism for MS in strong acids. The investigation has been done by analysing the articles published on the use of natural materials for MS’s protection in acid media. The results of weight loss measurements (WLM), electrochemical measurements (ECM), surface analysis, and computational techniques in those articles were analysed and the inhibition mechanism has been discussed. This review article provides a clear and broad view of corrosion inhibition mechanisms and also gives suggestions to enhance the performance, which could be beneficial for the scientists and researchers working in this area.