Corrosion inhibition, surface and interface properties of thiophene-based compounds: A comprehensive review

Thiophene-based compounds have attracted significant attention in recent years for their outstanding corrosion protection properties. This comprehensive review documents the fundamental aspects of thiophene-based corrosion inhibitors, exploring their chemical structure, coordination bonding potential, adsorption mechanisms, and protective capabilities on various metals and alloys of industrial interest. A critical analysis of existing literature shows the capacity of thiophene derivatives to decrease corrosion rates, improve surface protection and demonstrate inhibition efficiencies (%IE) mostly more than 95 % at relatively low concentration. The high %IE of thiophene derivatives can be correlated with the strong ligand property of the thiophene moiety, exhibiting σ-donor and π-acceptor properties. They use unshared electron pairs of sulfur and π-electrons of the thiophene ring to coordinate with metallic substrates efficiently. Through coordination bonding, their adsorption produces more robust and effective hydrophobic layers that impede corrosion. This insight aims to provide a systematic understanding of thiophene compounds as effective corrosion inhibitors, guiding the development of novel, sustainable protection strategies for metal and alloy systems in diverse industrial applications. Recent use of theoretical modeling revealed the importance of molecular structure, functional groups, and environmental factors in the excellent performance of thiophene-based inhibitors. The study focuses on thiophene-based corrosion inhibitors, combines theoretical modelling, and analyses hybrid systems. This article also highlights shortcomings in practical application performance, industrial-scale validation, long-term environmental safety, and toxicity studies, while proposing directions for future research and industrial implementation.