Remarkable promotion of photocatalytic hydrogen evolution from water on TiO2-pillared titanoniobate

TiO2-pillared titanoniobate TiO2/HTiNbO5 as an efficient photocatalyst was prepared via an exfoliation–restacking route. The as-prepared nanohybrid is mesoporous with a high specific surface area of 171 m2/g and a gallery height of 1.55 nm. Under a 300 W Xe lamp irradiation, the nanohybrid exhibited a high photocatalytic activity of 219 μmol/h/(g cat) in splitting water into hydrogen, which is 12 times as high as its parent HTiNbO5 (18 μmol/h/g) and 24 times as TiO2 (9 μmol/h/g). Enlarged surface area and effective electronic coupling between the host and the guest components contribute to the high photocatalytic activity of TiO2/HTiNbO5. Its photocatalytic activity was further improved through platinizing, and 5 wt% Pt-loaded TiO2/HTiNbO5 gave a remarkable hydrogen evolution rate of 4735 μmol/h/g. A photoexcitation model of the semiconductor–semiconductor pillared photocatalyst was proposed based on the results of XPS and UV–vis.