Preparation Of CeO₂/TiO₂ Composite Nanomaterials And Its Photocatalytic Activity Research

As the green,cheap,high quality and recyclable properties,semiconductor photocatalyst provides a new research direction to solve the energy exhaustion and environmental problems efficiently using solar energy.Among various semiconductors,nano-TiO₂ is widely used in wastewater treatment and air purification due to its high chemical stability,nontoxicity,corrosion resistance and low cost.However,the narrow spectral response range and low quantum efficiency limit the industrial application of nano-TiO₂.Therefore,it is important to broaden the spectral response range and improve the quantum efficiency for the research of semiconductors photocatalysis.Combined the photocatalytic mechanism,we employed morphology design to improve the quantum efficiency.Besides,coupled semiconductor with nano-ceria was also prepared which can not only expand the asorption spectrum to the visible region,but also insulate the electron and holes.The research details were as follows:?1?Employing hydrothermal method to synthesize hierarchical TiO₂nanomaterials.We studied the influence of parameters on the sample's morphology,such as acid type,reaction temperature and time,et al.The crystal transition and growth mechanism were also discussed.Besides,a complex dye solution with Rhodamine B and methylene blue was used as simulated pollutant to examine the photocatalytic performance under untraviolet light.The effect of BET surface and exposed facets were also explored.?2?Using hydrothermal co-precipitation method to synthesize CeO₂/TiO₂ nanocomposites on the basis of existing TiO₂ nanomaterials.After the loading of CeO₂,the nano-TiO₂ maintained the original morphology,and the nano-CeO₂ was well-deposited on the surface of TiO₂.A series of materials with different mole mass were prepared and the photocatalytic performances were measured by photodegradation of methyl orange?MO?.The catalytic activity of CeO₂/TiO₂ nanocomposites under UV-light was improved.Besides,the new material had response to visible light,and the highest degradation efficiency was reached to 85%in2 h.?3?First,TiO₂ microspheres composed of nanosheets were prepared using solvothermal method.Then,the TiO₂ nanobelts were added to the reaction solution to obtain the string.Under the irradiation of untraviolet light,the performance of TiO₂ microsphere was superior to the commercial P25 powder,and samples obtained at 6h possessed the highest activity and good repeatability,which can reach to 95%in 30 min.At last,CeO₂/TiO₂nanocomposites were synthesized,which can photodegrade methyl orange up to 90%after 2 h under visible light irradiation.