Artificial photosynthesis aims at CO2 reduction for production of organics (e.g. CH3OH, CH4, HCOOH) by utilizing H2 from photocatalytic decomposition of H2O under solar radiation. To achieve this, photoexcitation of catalytic semiconductors with Highly Reductive Conduct Band (HRCB) energies is required, at strong reduction potentials from -100mVolts to -1900mVolts (vs. SHE). In this context, while the development of photocatalytic nanostructures with ECB up to -100mV has been achieved based on nanoxides, the shift of ECB to more reductive potentials (<-500mV) is much more difficult. The present nARTPHOTO proposal aims at the targeted development of new photocatalytic nanostructures based on innovative HRCB metal suboxides. The development of the new nanosuboxides will be done with Reductive Flame Spray Pyrolysis (R-FSP) technology, that has been developed in the Lab of Physical Chemistry of Materials & Environment of UoI. The structures to be developed are based on Z-heterojunctions comprising three components [nanoOXide] / [nano-SUBoxide]/ [metallic plasmonic particle] to be produced by Double-Nozzle FSPtechnology. The Oxidation Nozzle of the FSP reactor will produce the Nano Oxides and Reducing FSP Nozzle will produce the suboxic and the metallic plasmon particles in one step. Specific Z-heterostructures to be synthesized and studied are: [Nano-Oxides] = BiVO4, BiWO6, CuWO4 as photocatalysts of H2O dissociation at visible wavelengths, [Nano-Suboxides] = Cu2Ox, ZrO2-x, CuFe2O4, dopped-TiO2-x, dopped-TaO3 -x as HRCB photocatalysts. [Metallic particles, M0] = Au0, Pd0, Pt0, Ag0, Cu0, Ni0 and combinations thereof will be used for plasmonic amplification of catalysis, selectivity of products (to HCOOH, CH3OH) and exploitation of Hot-Electrons. The exploitation of photosensitive Hot-Electrons will be studied and optimized by Electronic Paramagnetic Resonance (EPR) and Raman spectroscopy. Thus, the present proposal has clear research and technological innovation combining industrial-scale DN-FSP technology, basic research by EPR and Raman spectroscopy to produce /optimize Z-heterostructures for artificial photosynthesis.
