Photocatalytic activity of Sn2M2O7 (M = Nb and Ta) pyrochlore oxides with blue LEDs irradiation

In this study, we have investigated the photocatalytic properties for pyrochlore-type oxides Sn2M2O7 (M = Nb and Ta) and their solid solutions. Although the volume of evolved H-2 is very low, Pt-loaded Sn2Nb2O7 and Sn2Ta2O7 showed photocatalytic activity for H-2 evolution from water under blue LEDs irradiation. The absorption edge of the Sn2NbxTa2-xO7 solid solutions was in a position between those of Sn2Nb2O7 and Sn2Ta2O7, and the band gap became narrow monotonically as the value of x increased. Although some variability was observed, there was not the clear dependence on the composition value of x. (C)2012 The Ceramic Society of Japan. All rights reserved.