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

Abstract

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.

Site-Isolated Molecular Iridium Complex Catalyst Supported in the 1-Dimensional Channels of Zeolite HSSZ-53: Characterization by Spectroscopy and Aberration-Corrected Scanning Transmission Electron Microscopy

“…These bands are assigned to δ CH , ν C−C−Cs , and ν COring , respectively, resembling those characterizing Hacac adsorbed on the zeolite. 11,12 Thus, the IR data indicate that acac ligands were dissociated from the iridium as a result of the reaction of the precursor with the acidic OH groups of the zeolite, forming chemisorbed iridium complexes.…”

Atomic layer deposition and properties of ZrO2/Fe2O3 thin films

“…ALD of ZrO 2 from ZrCl 4 and O 3 has been studied [ 14 ]. Reactions between Fe(acac) 3 adsorbing on zirconia surfaces [ 15 – 16 ] has been studied as well. Phase stabilization of ZrO 2 by Fe doping was investigated by using ALD [ 17 ].…”

Surfactant effects on the particle size of iron (III) oxides formed by sol–gel synthesis

“…7. The infrared broad peak in the 450-650 cm À1 spectral region can be attributed to various iron-oxide species, [31][32][33] and hence, the broad absorption could be decomposed into (at least) 3 main absorption bands: (i) The asymmetric Fe-O stretching vibration of b-FeO(OH) at 624 cm À1 (peak 1); (ii) The asymmetric Fe-O stretching vibration of c-Fe 2 O 3 at 536 cm À1 (peak 2), and (iii) The symmetric Fe-O stretching vibration of any of these species, and possibly also aFe 2 O 3 , at 495 cm À1 (peak 3) [34]. Unfortunately, these characteristic absorption bands reside at the lower end of the mid-IR range of our instruments, and hence, may be susceptible to artifacts due to beam cut-off [35,36].…”