Fabrication and characterization of Fe2O3-based nanostructures functionalized with metal particles and oxide overlayers

We report on the design of nanosystems based on functionalized alpha-Fe2O3 nanostructures supported on fluorine-doped tin oxide (FTO) substrates. The target materials were developed by means of hybrid vapor phase approaches, combining plasma assisted-chemical vapor deposition (PA-CVD) for the production of iron(III) oxide systems and the subsequent radio frequency (RF)-sputtering or atomic layer deposition (ALD) for the functionalization with Au nanoparticles or TiO2 overlayers, respectively. The interplay between material characteristics and the adopted processing parameters was investigated by complementary analytical techniques, encompassing X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), and energy dispersive X-ray spectroscopy (EDXS). The obtained results highlight the possibility of fabricating Au/alpha-Fe2O3 nanocomposites, with a controlled dispersion and distribution of metal particles, and TiO2/alpha-Fe2O3 heterostructures, characterized by an intimate coupling between the constituent oxides.