Preparation and enhanced photocatalytic activity of Pd-CuO/palygorskite nanocomposites

Silicate nanofibers (palygorskite, Pal) coated with CuO nanoparticles were prepared via a precipitation method using copper oxalate as a precursor and subsequently modified with PVP-Pd solution. Characterization by X-ray diffraction and transmission electron microscope demonstrated that the surfaces of the Pal fibers with 20-30 nm in diameter and 400-500 nm in length were uniformly decorated with CuO nanoparticles of 16 nm in average size. The CuO/Pal and Pd-CuO/Pal nanocomposites exhibited higher photocatalytic activities than the pure CuO for the photodegradation of methyl orange under UV-light. The enhanced photocatalytic activity of CuO/Pal and Pd-CuO/Pal composites may be ascribed to the surface adsorption and efficient electron-hole separation at the coupled interface. The combination of nanoparticles and nano-scale fibers can lead to a remarkable improvement in photocatalytic activity; this concept can be expected to find interesting applications in the environmental field. (C) 2012 Elsevier B.V. All rights reserved.