Enhanced photocatalytic activity of core shell SnO2/ZnO photocatalysts

Core shell SnO2/ZnO particles were synthesised and their photocatalytic activities were tested for the discoloration reaction of methyl orange. To illustrate the effect of the core/shell structure, two photocatalysts, coupled SnO2/ZnO particles and core shell SnO2/ZnO particles, were prepared by co-precipitation and successive precipitation method respectively. The results of methyl orange decoloration showed that core shell SnO2/ZnO photocatalysts with a Zn/Sn ratio of 0.5, exhibited a slightly higher photocatalytic activity than coupled SnO2/ZnO photocatalysts, which may be caused by the increase of charge separation efficiency. Moreover, a model explaining the improvement of the photocatalytic activity in the core shell sample was also discussed.