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TiO 2 –Au hybrid materials are promising as electrocatalysts for the in situ production of H 2 O 2 via the oxygen reduction reaction (ORR). However, the synthesis of uniform and well-controlled TiO 2 –Au materials, which is crucial to establish morphology–performance relationships, remains challenging. We describe herein the synthesis of hybrid materials composed of TiO 2 colloidal spheres and wires decorated with Au nanoparticles. We employed TiO 2 colloidal spheres and wires as physical templates for Au deposition, which enabled the uniform deposition of Au NPs with monodisperse sizes over the TiO 2 surface. Then, the electrocatalytic activities toward the electrogeneration of H 2 O 2 by the ORR were investigated as a function of the TiO 2 shape and TiO 2 –Au loading on Vulcan XC-72R carbon. We found that the electrocatalytic activities were strongly dependent on the TiO 2 shape and TiO 2 –Au loading in the catalysts. The utilization of TiO 2 colloidal spheres led to higher activities relative to pure carbon and commercial Pt/C, and the optimal TiO 2 –Au loading corresponded to 3%. Conversely, the TiO 2 wires led to detrimental effects over the catalytic performances for all hybrid materials. These results could be explained based on the morphological and conductivity differences among TiO 2 –Au/C electrode materials. We believe the results described herein can have important implication for the design of TiO 2 -based hybrid nanostructures for the electrogeneration of H 2 O 2 by the ORR. [ABSTRACT FROM AUTHOR]