Nanostructured materials for photoelecrochemical hydrogen production

Highly ordered TiO2 nanotubes (TiNTs) were produced via an anodization process. Nanoscale gold nanoparticles were deposited onto the TiO2 surfaces using a deposition-precipitation method. The addition of gold nanoparticles to the TiO2 nanotubes is expected to significantly improve the water oxidation activities. In addition to a modest improvement in the electrocatalytic properties, deposition of the Au nanoparticles caused a slight reduction in the TiO2 bandgap. This would allow the TiO2 to absorb more light in the visible portion of the spectrum. The performance of the TiNTs was compared to that for a commercial TiO2 powder (P25 from Degussa). The TiNT based electrodes achieved higher current densities than the powder based electrodes.