Recent advances in nanotechnology and colloidal synthesis procedures have enabled the synthesis of such closely packed nanostructures, including nano-chains, self-assembled films, and self-assembled supraparticles where nanoparticles form a single three dimensional entity unlike layered films. These structures can potentially provide a more effective platform for plasmon-plasmon and plasmon-semiconductor interactions compared to traditional composites with isolated nanoparticles. , For example, Herran et al. prepared a twodimensional bimetallic catalyst by incorporating platinum nanoparticles into a well-defined super-crystal of gold nanoparticles exhibiting an H2 evolution rate of 139 mmolg -1 h -1 . Shi et al. prepared self-assembled Au-CdSe nanocrystal clusters with a 10-fold enhancement in photocatalytic H2 evolution. Electrostatic self-assembly provides a straightforward and effective method for creating self-assembled structures. Research has demonstrated the versatility and effectiveness of electrostatic self-assembly in a broad range of applications, including photocatalysis. , In this study, electrostatic self-assembly aids in maintaining the nanoparticles' stability, with TiO2 at the surface and without the influence of ligands that could potentially block active sites. This is in strong contrast to surfactant-based self-assembly approaches where ligand coverage may hamper the availability of the active sites and as a result may decrease the photocatalytic activity. In the current study, the insights that plasmonic Au NPs facilitate H2O2 production, and the general concept that supraparticles can boost plasmon-plasmon and plasmon-semiconductor interactions, are combined and leveraged into the integrated solution of Au-TiO2 supraparticles (SPs) as a novel approach to enhance plasmon-enhanced photocatalytic H2O2 generation. The unique aspect of these SPs is their ability to facilitate collective plasmonic excitation, a phenomenon where the plasmonic response of the entire particle assembly is greater than the sum of its individual components. , This collective behavior is expected to enhance the plasmonic effects on the semiconductor, leading to more efficient energy transfer and improved photocatalytic performance. The synthesis of these SPs involves a controlled electrostatic interaction between poly(allylamine hydrochloride)-coated Au nanoparticles and titanium ammonium lactate hydroxide (TALH). This process not only allows for the formation of the SPs but also offers a tunable approach to manipulate their size, which is crucial for optimizing their photocatalytic activity. Surface Enhanced Raman Spectroscopy (SERS) and radical trapping experiments involving Electron Paramagnetic Resonance (EPR) Spectroscopy and different probe molecules give an understanding that the enhancement can primarily be attributed to a combination of near-field enhancement and associated hot-electron injection from the Au nanoparticles to TiO2, facilitating the electron-mediated photocatalytic ORR of O2 to H2O2. These results not only demonstrate the potential of Au-TiO2 SPs in plasmon-enhanced photocatalysis but also provide valuable insights into the design of more efficient plasmonic photocatalytic materials.