Jinxiu Wang

ZnO photonic crystals with enhanced photocatalytic activity and photostability

ZnO photonic crystals (ZnO-PCs) with large area and high quality were prepared by a facile auto-forced impregnation method. The resulting ZnO-PCs exhibited remarkable photocatalytic performance and photocorrosion inhibition compared with porous and commercial nanoparticle ZnO.

Probing photonic effect on photocatalytic degradation of dyes based on 3D inverse opal ZnO photonic crystal

3D inverse opal ZnO photonic crystals (ZnO-PCs) with designed photonic bandgap (PBG) were prepared to study the pore size and slow photon effect on photocatalytic dye degradation. The PBGs of these ZnO-PC films were tuned experimentally by variation of the polystyrene sphere size of the opal templates. It was found that there is competition between the surface area and mass transport with increasing pore size during photocatalysis. ZnO-PCs exhibited higher photocatalytic activity under visible light irradiation, when the probe molecules were absorbed and well matched with the PBG. The enhancement could be attributed to intensified dye photosensitization as a result of the slow photon effect at the PBG edges, thus leading to a remarkable improvement in the light trapping. The present results provide useful information for developing high performance photocatalysts and photoanodes based on artificial photonic crystal design.

One-step template-free synthesis of BaSb2O6 micro-flowers and their associated photocatalytic activity

The rose-flower-like BaSb2O6 (R-BaSb2O6) and marigold-flower-like BaSb2O6 (M-BaSb2O6) have been successfully prepared by a simple hydrothermal method avoiding high temperature, templates, catalysts, surfactants, or organic solvents. Their structures and morphologies have been investigated by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and selected-area electron diffraction. Ba/Sb molar ratio and pH values in the precursor play significant roles in building two kinds of flower-like BaSb2O6. Time dependent experiments reveal the possible formation mechanisms of the BaSb2O6 microstructures. When used as a photocatalyst, the M-BaSb2O6 exhibits the best photocatalytic activity among R-BaSb2O6, M-BaSb2O6 and BaSb2O6 synthesized by solid state reaction. The morphology of M-BaSb2O6 results in the large BET specific surface area and unique light propagation mode, which greatly improve the interaction among photons, organic compounds and photocatalyst, and thus enhance photocatalytic activity. The photocatalytic stability experiments demonstrate the sufficient stability of M-BaSb2O6 during the photocatalytic process.