Zirconium-based nanocatalysts by sputtering onto glycerol and solid carbon
Résumé
Zirconia-based compounds has gained significant attention as a potential catalyst material for the oxygen reduction reaction (ORR) due to its high electrochemical stability in acidic media and oxidative atmospheres [1]. The formation of oxynitride and under-stoichiometric compounds by nitrogen doping and oxygen vacancy introduction seems to enhance the ORR catalytic activity [2]. In this study, ZrOx and ZrOxNy materials were synthesized using two techniques: i) the direct deposition onto carbon support (plane and porous) by reactive magnetron sputtering (rMS) assisted to an inductively couple plasma (ICP) and ii) the growth of nanoparticles inside glycerol by the reactive magnetron sputtering onto liquid (rMS-SoL) technique (adapted for Pt catalyst [3]). Various gas compositions (Ar + O2 + N2) were used and small amount of H2 admixture was employed in order to enhance the formation of excited and ionized nitrogen species. The properties of the catalytic materials were investigated by Rutherford backscattering spectroscopy, electron energy loss spectroscopy and nuclear reaction analysis (composition), scattering electron microscopy, X-ray diffraction and high-resolution transmission electron microscopy (morphology and nanostructure). Finally, the ORR catalytic activity was investigated for different nanostructures, morphologies and compositions. These findings provide insight into the potential of ZrOxNy as a cost-effective and efficient catalyst for fuel cell, and could pave the way for further research in this field.
Acknowledgement: This work has been funded by the French National Research Agency through the InnOxiCat project (ANR-20-CE05-0010).
Keywords: Magnetron sputtering, sputtering onto liquid, oxinitride, catalyst, oxygen reduction reaction
References:
[1] A. Ishihara et al., Emergence of Oxygen Reduction Activity in Zirconium Oxide-Based Compounds in Acidic Media. J. Phys. Chem. C 2019, 123, 30, 18150–18159.
[2] M. Chisaka et al., Zirconium Oxynitride-Catalyzed Oxygen Reduction Reaction at Polymer Electrolyte Fuel Cell Cathodes, ACS Omega 2 (2017) 678.
[3] V. Orozco-Montes et al., Synthesis of Platinum Nanoparticles by Plasma Sputtering onto Glycerol: Effect of Argon Pressure on Their Physicochemical Properties, J. Phys. Chem. C 2021, 125, 5, 3169–3179.