Comparative study on corrosion behavior of Cu and Sn under UV light illumination in chloride-containing borate buffer solution

Corrosion behaviors of copper and tin in chloride-containing borate buffer solutions (pH 8.4) were investigated through electrochemical and spectroscopic techniques in the presence and absence of UV illumination. Concerning effects of UV light on the corrosion processes, in a borate buffer solution containing 0.025 M NaCl, photoenhanced pitting corrosion was observed on copper while photo-induced passivation was found on tin. The effect of UV illumination on corrosion was dependent on the interaction between the photo-generated carriers and the metal oxides, as well as the photostability of the oxide film. Chloride anions can decrease the photostability of the oxide film.

Automated summary

The corrosion behaviors of copper and tin in chloride-containing borate buffer solutions under UV illumination were studied. It was found that copper exhibited photoenhanced pitting corrosion while tin showed photo-induced passivation in a borate buffer solution containing 0.025 M NaCl. The effect of UV illumination on corrosion depended on the interaction between photo-generated carriers and metal oxides, as well as the photostability of the oxide film. Chloride anions were observed to decrease the photostability of the oxide film.