Preparation Of3DOM Composite And Photocatalytic Performance

The different types of three-dimensionally ordered macroporous （3DOM） compositephotocatalytic composites in this study were prepared by template and sol-gel methodcombined with post-processing methods of calcinations:3DOM Ag/ZnO-TiO₂、3DOMAg/ZrO₂-TiO₂and3DOM ZnO/ZrO₂-TiO₂（P123）. Polystyrene micrspheres （PS） is a templateused during the preparation of3DOM Ag/ZnO-TiO₂and3DOM Ag/ZrO₂-TiO₂.3DOMZnO/ZrO₂-TiO₂（P123） composite was prepared using dual templates of polystyrenemicrospheres and EO₂₀PO₇₀EO₂₀（P123）. The phase composition, structures and morphologieswere well-characterized via Fourier transform infrared （FT-IR） spectrum, X-ray diffraction（XRD） patterns, X-ray photoelectron spectra （XPS）, N2adsorption-desorption tests andscanning electron microscopy assisted X-ray energy dispersive spectroscopy （SEM-EDS）.The results showed that the composites had three-dimensional macroporous structures andpore structures distributed neat and orderly. Compared with the size of PS microspheres, thepore size of composites had some contraction, moreover, the walls structure of compositeswas mesoporous. Silver species existing in the3DOM Ag/ZnO-TiO₂and3DOMAg/ZrO₂-TiO₂were metallic Ag0and well distributed on the catalyst surface. Compared withthe above composites, the average pore size of3DOM ZnO/ZrO₂-TiO₂（P123） was relativelysmall（3.8nm）, and BET surface area was relatively large（202.8m2/g）, inaddition its poreshrinkage was about50%.To investigate the photocatalytic activities of the three-dimensional ordered macroporouscomposites, some experiments were studied. Firstly, the photocatalytic activities of3DOMAg/ZnO-TiO₂were studied by the micro-assisted photocatalytic degreadation of methylorange, methylene blue and malachite green as a model molecule. Secondly, thephotocatalytic activities of3DOM Ag/ZrO₂-TiO₂and3DOM ZnO/ZrO₂-TiO₂（P123） werestudied with different structures of the dye under UV irradiation. The results showed that thethree-dimensional ordered macroporous composites all exhibited high photocatalytic activitiesfor the dyes with different structures, which was significantly higher than that ofone-component system, binary system and three-component system without PS treatment, andshowed that its photocatalytic ability was also widely applied on the degradation of dye.