Improvement of photocatalytic activity of TiO2 nanoparticles on selectively reconstructed layered double hydroxide (original) (raw)
2012, Applied Catalysis B: Environmental
Supported TiO 2 nanoparticles have been successfully fabricated by selective reconstruction of a Cu 2+ , Mg 2+ , Al 3+ , Ti 4+-containing layered double hydroxide (CuMgAlTi-LDH) precursor, synthesized by coprecipitation, through calcination and rehydration process. A systematic investigation of the structural characterization and the photodegradation tests of methylene blue (MB) dye molecules from solution under both UV and visible light irradiation for the resulting TiO 2 /CuMgAl-RLDH sample were carried out. Anatase-type TiO 2 nanoparticles are found to be homogeneously distributed on the surface of the selectively reconstructed CuMgAl-RLDH support. And the direct evidence for the surface TiO 2 /LDH heterojunction formed on CuMgAl-RLDH is presented. For MB photodegradation under UV light or visible light illumination, TiO 2 /CuMgAl-RLDH sample has superior photocatalytic properties to the rehydrated single phase R-TiO 2 , the physical mixture of R-TiO 2 and CuMgAl-RLDH, the composite CuTi/MgAl-RLDH synthesized by the rehydration of mixture of MgAl-MMO and CuTi-MMO, and the TiO 2 /MgAl-RLDH prepared under the same procedure as TiO 2 /CuMgAl-RLDH without containing Cu ions. The skeleton Cu 2+ ions dispersed in the mainlayer of CuMgAl-RLDH support can enable the photocatalytic activity for MB photodegradation. The TiO 2 /LDH heterojunction nanostructure is proposed to contribute the efficient spatial separation between the photogenerated electrons and holes, which can concomitantly improve the photocatalytic activity. Our method provides a novel approach to fabricate new modes of load-type doped semiconductor photocatalysts which are both active under illumination by UV and visible light.
Loading Preview
Sorry, preview is currently unavailable. You can download the paper by clicking the button above.