We use plasmonic Au TiO2 aerogels as a platform in which to marry synthetically thickened particle particle junctions in TiO2 aerogel networks to AuliTiO(2) interfaces and then investigate their cooperative influence on photocatalytic hydrogen (H-2) generation under both broadband (i.e., UV + visible light) and visible-only excitation. In doing so, we elucidate the dual functions that incorporated Au can play as a water reduction cocatalyst and as a plasmonic sensitizer. We also photodeposit non-plasmonic Pt cocatalyst nanoparticles into our composite aerogels in order to leverage the catalytic water-reducing abilities of Pt. This Au Ti0(2)/Pt arrangement in three dimensions effectively utilizes conduction band electrons injected into the TiO2 aerogel network upon exciting the Au SPR at the AullTiO(2) interface. The extensive nanostructured high surface area oxide network in the aerogel provides a matrix that spatially separates yet electrochemically connects plasmonic nanoparticle sensitizers and metal nanoparticle catalysts, further enhancing solar-fuels photochemistry. We compare the photocatalytic rates of H-2 generation with and without Pt cocatalysts added to Au TiO2 aerogels and demonstrate electrochemical linkage of the SPR-generated carriers at the AullTiO(2) interfaces to downfield Pt nanoparticle cocatalysts. Finally, we investigate visible light stimulated generation of conduction band electrons in Au TiO2 and TiO2 aerogels using ultrafast visible pump/IR probe spectroscopy. Substantially more electrons are produced at Au TiO2 aerogels due to the incorporated SPR-active Au nanoparticle, whereas the smaller population of electrons generated at Au-free TiO2 aerogels likely originate at shallow traps in the high surface-area mesoporous aerogel.