Abstract
New aspects of molecular interactions in corrosion inhibition are reported in this first investigation of benzotriazole on copper using surface enhanced Raman scattering (SERS). The observation of hysteresis in the Raman intensity of concentrated solutions as a function of applied voltage is attributed to a conformation or bonding rearrangement in the protective layer. Also, a photoalteration of the benzotriazole complex, which occurs during anodization, produces improved corrosion resistance and increases the Raman activity. The ability of SERS to detect these photoaltered layers provides a new probe for corrosion studies.