Au-assisted methanol-hydrogenated titanium dioxide for photocatalytic evolution of hydrogen

The development of efficient photocatalysts with extraordinary activity and robust stability is an eternal yet challenging goal for the conversion of solar energy to hydrogen. One effective and mild approach to facilitate the production of H atoms on TiO2 is to employ molecules such as CH3OH that can dissociate with much smaller energy barriers without the danger of contamination of the surface by C, which might decrease the photocatalytic activity of TiO2. A facile strategy based on hydrogenation of TiO2 with CH3OH in an Au-loaded system is here proposed for the exploration of excellent photocatalysts with ultrahigh activity and robust stability. Under solar illumination, Au loaded on hydrogenated TiO2 photocatalysts produced hydrogen at a rate 2.73 mmol h(-1) g(-1) with operational stability up to 50 h, significantly outperforming photocatalysts at the state of the art. Systematic studies using UV-vis, PL, Raman, XRD and XPS analyses indicated that, relative to conventionally hydrogenated TiO2 with H-2 as the hydrogen source, Au loaded on hydrogenated TiO2 using CH3OH as the hydrogen source significantly enhanced the activity and stability. The synergistic effect of the hydrogenation using CH3OH and Au decoration was investigated systematically and confirmed with synchrotronbased soft X-ray absorption spectra in situ.