Controlled Deposition of Iron Oxide on the Surface of Zirconia by the Molecular Designed Dispersion of Fe(acac)3: A Spectroscopic Study

The reaction of Fe(acac) 3 with the surface of zirconia has been studied for the first time using in situ infrared diffuse reflectance spectroscopy, photoacoustic spectroscopy, and Fourier transform Raman spectroscopy. The unstable Fe(acac) 3 reacts readily with the surface of zirconia at room temperature in the liquid phase or at 110 °C in the gas phase, yielding grafted Fe−OH species and Zr−acac surface groups. We present evidence that the reaction occurs both with coordinatively unsaturated Zr sites and with the surface hydroxyls. The grafted Zr−acac groups are thermally unstable and form Zr−acetate groups after thermal treatment at 110 °C in ambient air. After removal of the organic ligands, noncrystalline iron oxide species are formed on the zirconia surface. The grafting of iron oxide on zirconia is a relevant procedure to form either redox catalysts or solid-state fuel cells.