Infrared Spectroscopy in Corrosion Research

Infrared (IR) spectroscopy is a spectroscopic technique dealing with the interaction of IR light with molecules. Molecules absorb IR light that are characteristics of their structure and matches their vibrational frequency. The absorption, emission, and reflection of IR radiation are based on changes in vibrational or rotational energy states of molecules. The IR technique can analyze and identify gaseous, liquid, or solid samples of compounds. IR techniques have been used widely in corrosion studies and its control. In this chapter, we have highlighted the basic theory of IR spectroscopy, the different IR instrumentations, and techniques. Some selected studies reported in the literature on the application of IR technique to understand corrosion-related phenomena like corrosion inhibition, microbiologically induced corrosion, atmospheric corrosion, and coating and surface treatment are also presented.