Cobalt-phosphate/Ni-doped TiO2 nanotubes composite photoanodes for solar water oxidation

Surface modification and ions doping are the efficient ways to enhance photocatalytic activity of titanium oxide. The cobalt-phosphate/Ni-doped TiO2 nanotubes composite photoanodes were fabricated via electrodeposition method and its photocatalytic properties were investigated. The cobalt-phosphate/Ni-doped TiO2 composite photoanodes were characterized by scanning electron microscope, Raman spectrum, X-ray photoelectron spectroscopy and diffuse reflectance absorption spectra. The photocatalytic activity of the cobalt-phosphate/Ni-doped TiO2 composite photoanodes exhibited a remarkable improvement. The experimental results indicated that the onset potential of cobalt-phosphate/Ni-doped TiO2 composite photoanodes shifted to more negative position compared to that of the undoped TiO2. The photocatalytic performance of the cobalt-phosphate/Ni-doped TiO2 composite photoanodes is attractive for further investigation of solar water oxidation.