| Photocatalytic reactions of semiconductors such as splitting of water have received much attention from researchers because of their possible application to the conversion of solar energy into chemical energy. Especially, more and more layered compounds have been used as catalysts owing to their unique structural feature and excellent photocatalyitc activities.In this paper, the layered HLaNb2O7 that was doped with various metal elements such as molybdenum, chromiuma and indium were prepared by solid-stated reaction followed by an ion-exchange reaction; TiO2 and Pt were incorporated into the the interlayer of the host layer by successive soft chemical reaction processes under UV light irradiation. Then the samples obtained were characterized by TG-DTA, XRD, DRS, Specific surface area analysis and Atomic absorption spectrometry analysis. The results suggested that undoped HLaNb2O7 did not show absorption in the visible light region above 400 nm, while Mo (Cr, In)-doped HLaNb2O7 showed more or less broad absorption over 400-700 nm. Moreover, TiO2 and Pt nanoparticle were pillared in the interlayer of the host layer.The photocatalytic activities of the samples were measured by the hydrogen gas production rate from 500 ml of 0.1 M methanol solution containing 1 g of dispersed catalyst under irradiation from a 100 W mercury lamp. The results indicated that Mo (Cr, In)-doped HLaMb2O7 /Pt showed excellent hydrogen evolution activity and the activity was impacted by the doping concentration. When the doping concentration of Mo (Cr, In)-doped HLaNb2O7/Pt was Mo/Nb = 2.5 mol %, Cr/Nb = 5 mol % and In/Nb = 5 mol %, the hydrogen evolution rate was 2.9 mmol·h-1, 3.2 mmol·h-1 and 4.5 mmol·h-1 respectively; while the hydrogen evolution rate of undoped HLaNb2O7 /Pt was just 2.0 mmol·h-1. Therefore, doping the host layer with metal elements was a effective method to enhance the photocatalytic activity of the catalysts.
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