Suspensions of titanium dioxide catalysts decorated with plasmonic metal nanoparticles (NPs) are widely investigated in view of photodegradation of a variety of contaminants in water under irradiation with visible light. In this work, we used porous TiO2 electrodes bearing gold NPs to carry out photooxidation of model organic molecules either using oxygen as scavenger of photogenerated electrons or under imposed anodic bias. In both cases, continuous decrease of visible light photoactivity consistent with the drop of incident photon-to-current efficiencies (IPCEs) of the Au/TiO2 photocatalyst was observed. (C) 2017 The Electrochemical Society. All rights reserved.