Photocatalytic property of a keggin-type polyoxometalates-containing bilayer system for degradation organic dye model

The photocatalytic activity composite films incorporating the Keggin-type polyoxometalates (POM) K6CoW12O40·16H2O and K3PW12O40·nH2O (MW12 (M = P, Co)) and [Cu(II)(1,8-dimethyl-1, 3, 6, 8, 10, 13-hexaazacycloteradecane)]2+(L) have been prepared by the layer-by-layer (LbL) self-assembly method. The experimental results show that the deposition process is linear and highly reproducible from layer to layer. Atomic force microscopy (AFM) images of the L/MW12 composite films indicate that the film surface is relatively uniform and smooth. In addition, the films show high photocatalytic activity to the degradation of organic dye model (methyl orange (MO)), attributed to the formation of an O → W charge-transfer excited state at W–O–W bridge bond, resulting in generating highly reactive holes and electrons; The photocatalytic efficiency of the films have little change after several times of photocatalytic cycle, indicating that the composite films are stable, reused and recovered.

POM-containing films via alternate adsorption of cationic L and anionic MW12 (M = P, Co) clusters were prepared on solid substrates. The photocatalytic property of the films was investigated.Figure optionsDownload as PowerPoint slide