Study On Bimimeticsynthesis And Photocatalytic Performance Of Au/CeO₂ And Zn₃?PO₄?₂ Micro/nano Material

With the development of global industry,serious environmental pollution has become one of the major challenges we face.Photocatalytic technology is one of the important ways to solve environmental pollution because of its low energy consumption,high efficiency,cleanliness and environmental friendliness.It has become one of the research directions in the field of sewage treatment.Cerium oxide with cubic fluorite structure has the ability to store/release oxygen and is the same N-type semiconductor material as TiO₂.It not only absorbs ultraviolet light but also absorbs visible light in the near ultraviolet region,and can be better used as photocatalyst.Zinc phosphate,as a commonly used inorganic material,can also be used in the field of photocatalysis,when it has a special microporous structure.In this paper,CeO₂ and Zn₃?PO₄?₂ amples with special morphologies were prepared by biomimetic method under different conditions.Moreover,Au / CeO₂ photocatalyst was prepared by using cerium oxide as the carrier.The samples were characterized by XRD,SEM,FESEM,TEM,BET,UV-DRS and PL.The photocatalytic activity of each sample was studied when organic pollutant rhodamine B is used as the degradation target.The main research contents are as follows:?1?The CeO₂ samples with hierarchically structured morphologies such as bead on abacus,cotton ball and music instrument plectrum,were prepared by using bionic synthesis method,if Ce?NO₃?₃·6H₂O as precursor and L-cysteine hydrochloride as template.Au/CeO₂ photocatalysts were prepared by simple and gentle method at room temperature using the prepared CeO₂ samples as carriers.The effects of pH value and the ammount of added L-cysteine hydrochloride on the crystal phase,surface morphology and photocatalytic activity of the synthesized photocatalyst were investigated.The prepared Au/CeO₂ photocatalyst was used to degrade rhodamine B under the visible light.The results showed that the addition ammount of L-cysteine hydrochloride was 3 mmol,and the photocatalyst with the beads-on-abacus shape prepared at p H = 10 is more active.?2?CeO₂ sample with plane-tree-ball morphology,which is made up by nanorods with 100 nmdiameter,were prepared using Ce?NO₃?₃ · 6H₂ O and NaOH as raw materials and mannitol as template.Au/CeO₂ photocatalyst was prepared by sedimentation precipitation method.The degradation rate of rhodamine B was 97% by visible light irradiation.?3?Zn₃?PO₄?₂ photocatalyst was prepared through hydrothermal method,when zinc sulfate and phytic acid were used as raw materials.The pH value and concentration of precursor have great effects on the morphology,crystallinity and photocatalytic activity.The results demonstrated that the flower-like zinc phosphate with hierarchical architecture,had a hiher photocalytic activity.