Construction of Z-scheme type CdS-Au-TiO2 hollow nanorod arrays with enhanced photocatalytic activity

The Z-scheme type CdS-Au-TiO2 hollow nanorod arrays have been constructed on glass substrates by following these simple steps: firstly, highly ordered TiO2 hollow nanorod arrays (THNAs) were synthesized by liquid phase deposition (LPD) using ZnO nanorod arrays as templates; then both Au core and US shell nanoparticles were achieved on the THNAs by in situ photodeposition. The prepared three-component films were characterized by field-emission scanning electron microscopy (FSEM), high-resolution transmission electron microscope (HRTEM), Raman scattering and ultraviolet-visible absorption spectrum. The results showed that Au-CdS core-shell nanoparticles were well dispersed on wall of anatase THNAs from top to bottom. The three-component nanojunction system was evaluated for their photocatalytic activity through the degradation of methylene blue (MB) in aqueous solution. It was found that the CdS-Au-TiO2 three-component hollow nanorod arrays exhibited significantly enhanced photocatalytic activity compared with single (THNAs) and two components (Au-THNAs or CdS-THNAs) systems. Reasons for this enhanced photocatalytic activity were revealed by photoluminescence (PL) results of our samples. (C) 2009 Elsevier B.V. All rights reserved.