Recovery of platinum group metals into (electro)catalytic nanoparticles by gas-diffusion electrocrystallization (GDEx)

The aim of this project is to develop a new methodology to synthesize metallic and metal oxide nanoparticles with well-defined properties by reducing or oxidizing agent which are produced in-situ by means of an electrochemical reaction on a gas diffusion electrode.  From former results obtained in our group, there is a strong indication that when a proper gas is reduced in an electrochemical cell using gas diffusion electrodes as cathodes, reactive species are produced which reacts with metal ions in solution to produced nanoparticles. The nature of the nanoparticles will depend of the nature of the reactive species.  If CO2 is reduced, reducing agents such as CO and HCOOH are produced and metallic nanoparticles are synthesized. On the other hand, when O2 is reduced, a strong oxidant, H2O2, is produced and metal oxide nanoparticles are synthesized. Furthermore, by controlling parameters parameter such, working potential, pH, charge, gas flow, electrolyte composition,… is possible to modify the production rate of the reactive species which has an impact on the properties of the nanoparticles. Hence, it is also possible tailor their properties.   Noble metal nanoparticles (Pt, Pd, Rh, Au, Ag) for the production of catalysts for the electrochemical reduction alcohols in alcohol fuel cells and iron oxide nanoparticles for the production of agents for magnetically induced hyperthermia in cancer treatments are target in this project.