Optical and structural properties of Al2O3 doped ZnO nanotubes prepared by ALD and their photocatalytic application

Al2O3 doped ZnO nanotubes with controlled ratio of Al2O3 were successfully designed by combining the two techniques of atomic layer deposition (ALD) and electrospinnig. In order to study the effect of Al2O3 doping on optical and structural properties of Al2O3 doped ZnO nanotubes, the prepared samples were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared (FTIR), reflectance emission and room temperature photoluminescence (PL). The photocatalytic activity and stability of these materials under UV light was studied by the photodegradation of methyl orange (MO). The results indicate that Al2O3 doping increases the disorder (defects and oxygen vacancies formation) in the ZnO nanostructure which improves the separation efficiency of electron-hole pairs and therefore enhances the photocatalytic activity (5 times higher) and stability of Al2O3 doped ZnO in comparison with pure ZnO nanotubes.