[en] Conventional electrochemical methods as well as photoelectrochemical characterisations (PEC), performed ex-situ et in-situ, were used to study the Shadow corrosion phenomenon, considered as a galvanic corrosion between Zr-based and Ni-based alloys. The Shadow corrosion is influenced by the chemical environment and the irradiation of these alloys. An electrochemical cell, simulating the conditions of a boiling water reactor (BWR), allowing the illumination of the samples with UV-Visible as well as monitoring the water chemistry was designed, developed and validated. The cell allowed, for the first time, recording of in-situ photocurrent energy spectra on a Zr-based alloy in simulated BWR environment. Furthermore, the obtained experimental results pointed out that the metallic cation impurities played an important role in the activation mechanism of the galvanic coupling, thus potentially in the activation mechanism of the Shadow corrosion phenomenon, whereas the presence oxygen and/or hydrogen peroxide did not induce significant differences in terms of electrochemical behavior of the samples. It was also shown that the illumination of the sample with UV-visible light, which significantly amplified the galvanic current, is an important parameter of the Shadow corrosion phenomenon. (author)