Visible light promoted photocatalytic water oxidation: effect of metal oxide catalyst composition and light intensityElectronic supplementary information (ESI) available: SEM, Raman analysis, UV-vis spectroscopy, TEM, XRD, example calculations. See DOI: 10.1039/c5cy01203a

A range of low-cost nanoparticulate mixed transition metal oxides were prepared using a simple methodology and used as catalysts in visible light promoted water oxidations. The effect of catalyst and daylight equivalent light intensities on reaction efficiency in terms of O 2 yields, TOF and proton production was determined. Simply prepared low-cost nanoparticulate transition metal oxides were used as catalysts in visible light promoted water oxidations. The activity using daylight equivalent light intensities was assessed.