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We report on H2 generation by photocatalysis driven by simulated white light by electronically integrated Au nanoparticles with multifunctional, disordered mesoporous TiO2− xN x (Au-NT) nanocomposites. Solar H2 generation (1.5 mmol h−1 g−1) from aqueous methanol has been demonstrated with Au-NT nanocomposites. The water splitting activity of Au-NT is attributed to the 21.1 ps lifetime of charge carriers observed from fluorescence lifetime measurements, which indicates a high electron-injection efficiency from nano-Au to the conduction band of TiO2, and hence charge separation as well as utilization. This is directly supported by the observation of a high photoluminescence emission intensity with Au-NT that highlights the energy transfer from nano-Au to TiO2. The p-n heterojunction observed between the Au (0 0 1) and TiO2 (1 0 1) facets helps towards the higher charge separation and their utilization. A low mesochannel depth (<10 nm) associated with disordered mesoporous TiO2− xN x helps the charge carriers to move towards the surface for redox reactions and hence charge utilization. Visible-light absorption, as a result of the surface plasmon resonance of nano-Au, is observed in a broad range between 500 and 750 nm, which helps in harvesting visible-light photons. Finally, electronically integrated nano-Au with TiO2− xN x in Au-NT is evident from Raman and X-ray photoelectron spectroscopy measurements. All of these factors help to achieve a high rate of H2 production. It is likely that a higher rate of H2 production than that reported here is feasible by strategically locating Au clusters in porous TiO2 to generate hot spots through electronic integration. [ABSTRACT FROM AUTHOR]