UV-visible spectroscopy combined with differential and potential-modulated reflectance methods is one of the most versatile of currently available spectroelectrochemical techniques, because it provides sensitive detection of very thin films on electrode surfaces in the bulk solution and deals information on the formation process, the structure and properties of the films. The theory and experimental methods of this technique were explained and following typical examples were reviewed: anodic dissolution products, submonolayer metal deposits, organic adsorbates, and passive films on metal electrodes.
