Metal/TiO2 hierarchical nanocomposite arrays for the remarkable enhancement of photocatalytic activity

Metal/TiO2 hierarchical nanocomposite arrays were assembled by the deposition of aggregated TiO2 nanoparticles on anodic aluminum oxide templates and the subsequent loading of metal nanoparticles by electrochemical deposition. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and ultraviolet-visible spectroscopy. The photocatalytic activities of the as-synthesized catalysts were evaluated for the degradation of organic dyes. Our experimental results demonstrated that the greatly improved photocatalytic efficiency of the metal/TiO2 hierarchical nanocomposite arrays resulted from their high surface area and symmetrical arrangement. As a prospective approach for wastewater purification, our work not only enriches the synthetic methodology for TiO2, but also provides valuable knowledge about nanosized photocatalysts.