The objective of this study is to investigate the contribution of light energy in the electrochemical oxidation treatment of a solution containing a model molecule, Acid Blue 9 dye (AB 9) using a low-cost electrode elaborated by electrodeposition from a lead salt. The elaboration procedure and the characteristics of the obtained Ti/b−PbO ₂ electrode are given in the supplementary information. First, electrolysis and I-E curves were performed in order to determine the best conditions for dye removal and mineralization. Then the effect of illumination is studied.