Preparation of Cu-loaded SrTiO_3 nanoparticles and their photocatalytic activity for hydrogen evolution from methanol aqueous solution

摘要

Cu-loaded SrTiO_3 nanoparticles (Cu-SrTiO_3) were prepared using a simple in situ photo-deposition method and their photocatalytic activity for hydrogen evolution from methanol aqueous solution was evaluated. The results characterized with XRD, TEM, XPS and EDX indicated that the as-synthesized sample was composed of metallic Cu and cubic SrTiO_3, and the metallic Cu was homogeneously loaded on the surface of SrTiO_3 nanoparticles. Under UV light irradiation, Cu-SrTiO_3 displayed much higher photocatalytic activity for hydrogen evolution and excellent stability in comparison with pure SrTiO_3 nanoparticles. The results further confirmed that the efficient separation of photogenerated electron/hole pairs was critical for the enhanced photocatalytic activity of Cu-SrTiO_3. Moreover, the rate of hydrogen evolution of 0.5 wt.% Cu-SrTiO_3 is comparable with that of 0.5 wt.% Pt-SrTiO_3 photocatalyst under optimum conditions, implying that the metallic Cu is an efficient alternative to Pt as a co-catalyst on SrTiO_3. The high photocatalytic activity, low cost and chemical stability mean that the Cu-loaded SrTiO_3 is a potential catalyst for the photocatalytic hydrogen evolution from methanol aqueous solution.