ABSTRACT
The main aim of the present chapter is to review the various analytical and characterization tools which have been used recently to study graphene (G) and graphene-based nanocomposites, as corrosion protection layers and coatings, at macro-, micro-, and nano-scale. These methods include microscopy, spectroscopy, thermal stability evaluations and electrochemical tests. Most recent developments and achievements on each method are presented, including some detailed information about the techniques and experimental conditions in which they have been utilized. Examples of the application of imaging techniques, including scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in the detection of microstructure of graphene-based composite coatings are provided. Applications of atomic force microscopy (AFM) in the assessment of the surface roughness and topography of graphene-based nanocomposite coatings are demonstrated. Concerning the spectroscopic methods, X-ray diffraction spectroscopy (XRD), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared reflection (FTIR) spectroscopy, Raman spectroscopy and confocal Raman microscopy (CRM) are discussed. Application of electrochemical techniques such as electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) tests in determining the corrosion protection efficiency is reviewed. Other corrosion assessment techniques, such as weight loss measurements and salt spray tests, are also briefly addressed. The chapter ends with some concluding remarks regarding the benefits and limitations of each technique, to provide a guide in choosing the appropriate set of complementary techniques for characterization of graphene-based coatings and their corrosion protection performance.
