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Mixtures and composites of Ag/Ag₂O and TiO₂ (P25) with varying mass ratios of Ag/Ag₂O were prepared, employing two methods. Mechanical mixtures (TM) were obtained by the sonication of a suspension containing TiO₂ and Ag/Ag₂O. Composites (TC) were prepared by a precipitation method employing TiO₂ and AgNO₃. Powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of Ag(0) and Ag₂O. The activity of the materials was determined employing methylene blue (MB) as the probe compound. Bleaching of MB was observed in the presence of all materials. The bleaching rate was found to increase with increasing amounts of TiO₂ under UV/vis light. In contrast, the MB bleaching rate decreased with increasing TiO₂ content upon visible light illumination. XRD and XPS data indicate that Ag₂O acts as an electron acceptor in the light-induced reaction of MB and is transformed by reduction of Ag⁺, yielding Ag(0). As a second light-induced reaction, the evolution of molecular hydrogen from aqueous methanol was investigated. Significant H₂ evolution rates were only determined in the presence of materials containing more than 50 mass% of TiO₂. The experimental results suggest that Ag/Ag₂O is not stable under the experimental conditions. Therefore, to address Ag/Ag₂O as a (photo)catalytically active material does not seem appropriate.