Surface-enhanced Raman scattering (SERS) spectroscopy of corrosion inhibitors: High-resolution detection, adsorption property, and inhibition mechanism

Corrosion inhibitors are widely employed to retard metal corrosion. Highly sensitive detection and adsorption mechanism analysis are the two important aspects for the systematic research of corrosion inhibitors. Surface-enhanced Raman scattering (SERS) spectroscopy has emerged as a promising tool for the high-resolution detection and inhibition mechanism analysis of corrosion inhibitors in recent decades, and is of considerable importance for their selection and optimization. This paper provides an overview of the SERS technique in the study of corrosion inhibitors adsorbed on noble metals (SERS active substrates) and transition metals (non-SERS active substrates). After surface roughening, the SERS enhancement of metal electrodes can be significantly improved, which intensifies the Raman signals of adsorbed inhibitors to provide sufficient information regarding the binding state and adsorption orientation. In addition to roughening the metal surface to obtain strong SERS signals, novel SERS sensors that can amplify the Raman signals of inhibitors regardless of the type or surface state of the metal substrates are introduced, which is conductive to facilitating the real-time detection of inhibitors. The challenges and future prospects of SERS technique in corrosion inhibitor research are discussed. In summary, SERS technique is expected to promote the research development and engineering applications of corrosion inhibitors.