ZnO and TiO₂ 1D nanostructures for photocatalytic applications

ZnO and TiO₂ 1D nanostructures (nanorods and nanotubes) were prepared by low-cost, low-temperature, solution-based methods and their properties and photocatalytic performance were studied. ZnO nanorod samples with titania and alumina shells were also prepared by solution-based methods, and their properties and photocatalytic performance were compared to that of bare ZnO nanorods. We found that ZnO and TiO₂ exhibited comparable photocatalytic performance. Faster dye degradation under simulated solar illumination was observed for ZnO, while under UV illumination faster degradation was observed for TiO₂. ZnO nanorods with titania shells exhibited inferior photocatalytic performance, while for alumina shells the performance was similar to bare ZnO. Reasons for observed differences are discussed, and the effect of the shell on photocatalytic activity is attributed to the changes in native defects at the ZnO surface/shell interface.