TiO2-Fe2O3 and Co3O4-Fe2O3 nanocomposites analyzed by X-ray Photoelectron Spectroscopy

The present work is focused on the characterization of TiO2-Fe2O3 and Co3O4-Fe2O3 nanocomposites, of potential interest as photoanodes for photoelectrochemical (PEC) water splitting triggered by solar light. In particular, Fe2O3 nanostructures were deposited onto fluorine-doped tin oxide (FTO)-coated glass substrates by plasma enhanced-chemical vapor deposition (PE-CVD), and functionalized by either TiO2 or Co3O4, obtained via atomic layer deposition (ALD) or radio frequency (RF)-sputtering, respectively. The resulting systems were investigated by complementary techniques in order to obtain detailed information on their structure and morphological organization. In particular, their chemical composition was analyzed through the use of X-ray Photoelectron and X-ray Excited-Auger Electron Spectroscopies (XPS and XE-AES). To this regard, detailed spectra for C 1s, O 1s, Fe 2p and Ti 2p (or Co 2p and Co LMM) regions are reported and discussed.