Photocatalytic hydrogen production by water splitting over Au/Al-SrTiO3

Visible light water splitting activity of Au-Al/SrTiO3 was tested in this work. Al/SrTiO3 was synthesized via solid state reaction while Au loading was done with homogenous deposition precipitation method. The effects of Au loading and Al doping were investigated in 10, 20 and 30% aqueous solutions of methanol, ethanol, and isopropyl alcohol. The methanol was performed better over 0.25%Au-1.0%Al/SrTiO3 at 20% alcohol concentration while the isopropyl alcohol resulted in better performance over the same catalyst at 30% concentration; the latter was also the best result obtained in this work with the hydrogen evolution rate of 347 μmol/h.gcat. Ethanol showed lower performance than other two alcohols. It was found from UV–vis analysis that Al doping increased the band energy of SrTiO3. XRD and XPS analyses clearly showed that the dominant structure was SrTiO3 in all samples. Au was found to be generally loaded as 30–40 nm particles by SEM.