Photoresponse of Visible Light Active CM-n-TiO2, HM-n-TiO2, CM-n-Fe2O3, and CM-p-WO3 towards Water Splitting Reaction

Photoresponses of visible light active carbon modified titanium oxide (CM-n-TiO2), hydrogen modified titanium oxide (HM-n-TiO2), carbon modified iron oxide (CM-n-Fe2O3), carbon modified tungsten oxide (CM-p-WO3) towards water splitting reaction are reported in this article. Carbon and hydrogen in titanium oxide were found to be responsible for red shift from UV region to visible region which in turn enhanced the photoconversion efficiency by an order of magnitude for water splitting reaction. Photocurrent densities and photoconversion efficiencies of regular n-TiO2 and CM-n-TiO2 towards water splitting reaction under monochromatic light illumination from a xenon lamp and sunlight were compared and found in reasonable agreement. These oxides were characterized by photocurrent measurements, UV-Vis spectra, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) and x-ray diffraction (XRD) studies and these results are also reported in this article.