Preparation And Photocatalysis Properties Of The α-Fe₂O₃@TiO₂ Core-shell Particles

Environmental pollution has become a major problem faced by all countries in the world.Among them,water orage pollution is particularly serious.Photocatalytic technology is a most hoping green technology to solve the technology problem of high energy consumption,low efficiency,environmental and environmental constraints of traditional pollution treatment methods.TiO₂ is considered as an ideal photocatalyst because of its suitable band potential,high chemical stability,safety and non-toxicity.In this paper,α-Fe₂O₃@TiO₂ core-shell nanoparticles were modified by two synthetic routes as tetrabutyl titanate was used as raw material andα-Fe₂O₃ was used as a hard template.One is that the ellipsoidα-Fe₂O₃@TiO₂ core-shell nanoparticles was successfully prepared through improved St（?）ber method,the other is 3D lamellar flower-likeα-Fe₂O₃@TiO₂ nanorods were synthesized by solvothermal method.The prepared materials were characterized,and the results showed thatα-Fe₂O₃@TiO₂ composite photocatalys were successfully synthesized.XRD showed that all of the materials haveα-Fe₂O₃ and anatase TiO₂.TEM displayed ellipsoidalα-Fe₂O₃@TiO₂particles synthesized by St（?）ber method were consist of TiO₂shell coating theα-Fe₂O₃ spindle.SEM showed that the structure ofα-Fe₂O₃@TiO₂ synthesized by solvothermal method was unique 3D layered flower-like nanorod.UV-Vis test proved thatα-Fe₂O₃@TiO₂ellipsoids andα-Fe₂O₃@TiO₂ nanorods had good absorption in UV and visible region.The photocatalytic degradation of Rh B was used to evaluate the photocatalytic performance.Compared with primitive single substance,the photocatalytic performance ofα-Fe₂O₃@TiO₂ ellipsoids andα-Fe₂O₃@TiO₂ nanorods was greatly improved.The degradation rate ofα-Fe₂O₃@TiO₂ellipsoids with 38 nm shell thickness can reached 63.51%after calcined in 6h illuminated.Under the same conditions,the photocatalytic activity of 3D lamellar flower-likeα-Fe₂O₃@TiO₂ nanorods was higher than that of ellipsoids,the degradation rate of Rh B can reach 99.61%.The remarkable photocatalytic activity is attributed to the formation of heterojunction,unique core-shell structure and larger specific surface area.In addition,a possible mechanism of photocatalytic degradation was proposed.In this paper,two kinds of different morphologiesα-Fe₂O₃@TiO₂ core-shell structure provided a new synthesis strategy for the application of TiO₂ in the photocatalysis field.