Surface Engineered Multicomponent Nanoparticles with Composition M@MOx, (M=Au,Cu,AuCu & MOx=Cu2O@ZnOxSyorFe2OxSy) for Photo-electrochemical (PEC) Hydrogen Evolution Reaction

To cope with the environmental concerns of increasing CO2 levels, there is an increasing need to improve/develop functional materials for the production of carbon neutral energy resources such as hydrogen fuel using photo-electrochemical (PEC) water splitting. Therefore, the design and synthesis of new materials capable of harvesting the maximum range of solar spectrum, electrically and chemically stable, with suitable band-edge potentials to split water are inevitable. This project aims to accomplish the synthesis of multicomponent nanostructured materials with compositions M@MOx where M=Au, Cu, or AuCu and MOx=Cu2O coated either with a thin shell of ZnOxSy or Fe2OxSy )or doped with transition metal cations like Fe or Zn), employing non-aqueous solution synthesis for the photo-electrochemical (PEC) water splitting reaction. Due to the low band gap ~2.1 eV of Cu2O and its suitable conduction band edge positions (-0.7 eV with respect to E2H+/H2) it is among the most favourite semiconductors available for PEC water splitting to produce H2. However, the small carrier diffusion length ~20-100 nm and self-photocorrosion upon photoexcitation when in contact with water has limited its use in practical applications. The proposed work will focus to overcome both impairments through (i) controlling the size of Cu2O below the limits of charge diffusion length and (ii) tailoring the surface of the Cu2O domain through a solution processed photostable thin shell or doping. The designed multicomponent nanoparticles will also enhance the visible light absorption efficiency and increase the charge separation upon photoexcitation (i) due to the presence of palsmonic domains, (ii) the Schottky barrier at the metal-semiconductor interface, and (iii) through a p-n junction due to the core shell structure of Cu2O@ZnOxSy or Fe2OxSy. Moreover, this project will compare the influence of the size of the plasmonic domains as well as the size and number of semiconductor components on the PEC water splitting efficiency.