Preparation And Photocatalytic Properties Of 3DOM Ti³⁺/TiO₂ And 3DOM TiO₂/CeO₂ Photocatalyst

With the great development of social economy and people's living standards,the more and more environmental problem aroused the attention of people,environmental problem became a huge resistance to improve the quality of life.As global resources become increasingly scarce,it is the general trend of human development to find energy that can be used efficiently and sustainably.Photocatalysis is a kind of technology that can convert solar energy into chemical energy and it have the characteristics of energy-saving,environment-friendlyandpollution-free.Therefore,semiconductor photocatalysis technology as a new cleaning technology came into being.TiO₂ is one of the most widely used photocatalyst,which has attracted the attention of many scholars.The band gap value of TiO₂ is 3.2 eV.Therefore,the absorption wavelength can only respond to the light waves in the ultraviolet region.however,ultraviolet light only accounts for 3%to 5%of the sun's light energy.In order to increase the absorption capacity of TiO₂ in visible light region,scientists have put forward a series of modification research theories,such as combinig with semiconductor photocatalyst of low gap value,doping metal or non-metal,controling of the catalyst microscopic appearance and so on.Photonic crystal is an artificial microstructure formed by periodic arrangement of media with different refractive index,because of its unique structure,the material has a limited effect on photons and produces a photonic bandgap.At the edge of the photon barrier,The group velocity of light is greatly reduced,there the retention time of photons on the surface of a material is thus increased.The photocatalytic activity can be greatly improved by applying this property of photonic crystals in the field of photocatalysis.The research work of this paper is summarized in the following three aspects:1?Preparation and research of SiO₂ and PS templates.In this study,the non-soap emulsion method was used to prepare the polystyrene microspheres of 265 nm and 220 nm,and the SiO₂ colloidal microspheres of 315 nm and 330 nm were prepared by the stober method,and the colloidal microspheres were assembled into colloidal crystal templates.The macroscopic properties and microscopic properties of the colloidal crystals are studied and the ordered structure of the surface centered cubic is obtained and the photonic band gap is produced.2?3DOM Ti³⁺Self-doped TiO₂ for Photocatalytic Removal of NOThree dimensional ordered macropore?3DOM?Ti³⁺self-doped TiO₂(3DOM Ti³⁺-TiO₂)was prepared by calcination using PS nanoparticles self-assembled as the template.The morphology,composition and pore structure of 3DOM materials were studied by SEM,XRD,PC,XPS and DRS.The surface of the material above has a six-sided ordered arrangement of large holes,by SEM and DRS,It is proved that the three-dimensional ordered macropore structure can regulate light absorption.For obtained 3DOM TiO₂,in order to expand the spectral response of the 3DOM TiO₂,we used ice-water quenching method doping Ti³⁺and made the detailed research of its structure,the research results show that Ti³⁺-TiO₂ photocatalysis rate is 3.5 times of powder TiO₂ under the visible light.3?Synthesis and Photocatalytic Performance of Three Dimension Ordered Macroporous TiO₂/CeO₂ Composite PhotoctatalystTiO₂/CeO₂ composite photocatalyst with three dimension ordered macroporous structure?3DOM TiO₂/CeO₂?was prepared by calcination and template etching via self-assembly of SiO₂ nanosphere as the template.The obtained photocatalyst was characterized by XRD,SEM,FT-IR,DRS and PC.The photocatalytic activity of 3DOM TiO₂/CeO₂ was studied by using rhodamine B as the degradation object under simulated sunlight irradiation.The result shows that the photocatalytic degradation activity of 3DOM TiO₂/CeO₂ is further improved compared with TiO₂/CeO₂.The reason of enhanced photocatalytic performance of 3DOM TiO₂/CeO₂ can ascribe to the 3DOM structure,which can produce slow photons effect and improve the light absorption ability of TiO₂/CeO₂ composite photocatalyst,and finally improve the photocatalytic properties of TiO₂/CeO₂.