UPconversion photocatalyst for H2 production by water splitting – UPH2

In order to produce hydrogen from completely de-carbonized sources, several solutions exist. The electrolysis of water using electricity produced by renewable means or the photolysis of water using a photocatalyst and light. It is also necessary that the light is produced by a de-carbonized source. More simply one can of course use the sun light directly and thus eliminate a conversion step. Unfortunately, photons useful for photolysis represent only a small proportion of the total photons received from the sun.
The UPH2 project aims at developing new photocatalysts for water dissociation that directly incorporate a light conversion functionality by addition of photons (up-conversion) in order to take maximum advantage of the solar spectrum.
For this purpose, we will study a family of rare earth doped oxysulfides, which allow up-conversion within the photocatalyst structure, and which will be synthesized by thermal decomposition of custom developed (hetero)-metallic precursors. These quaternary oxysulfides are already effective for the photodissociation of water down to wavelengths below 500nm (limited by the absorption of the matrix). The addition of an internal excitation conversion process via rare earth doping will increase the efficiency range of these photocatalysts to the near infrared and thus allow a significant increase in their efficiency under solar excitation.