Study On The Preparation Process And Photocatalytic Properties Of TiO₂ Doping With Fe/Cu/Ce-ions

Due to its high photocatalytic activity,stable chemical properties and strong oxidation properties,TiO₂ semiconductor material has become the most promising catalyst material.However,as a photocatalytic material,TiO₂ has two serious disadvantages:?1?in the process of catalysis,TiO₂ can only absorb very little ultraviolet light from the sun due to its wide banding width,?2?during the photocatalytic reaction of TiO₂,the electron and hole are easy to recombine.For this reason,the different content of Fe³⁺,Cu²⁺,Fe³⁺+Cu²⁺and Ce³⁺doped TiO₂ has been prepared by a sol-gel method,and it's microstructure,phase structure and properties has been analyzed.The conclusion is as follows:At a calcination temperature of 450?,TiO₂ powder was relatively tiny,and high temperature prompted TiO₂ grain size bigger,reunion phenomenon intensified.TiO₂powder doping with Fe³⁺was mainly composed of anatase phase,and rutile phase gradually turned into anatase phase.With Fe³⁺doping amount adding,rutile phase began to increase.Fe³⁺refined the grain size of TiO₂ and reduced agglomeration.A large amount of hydroxyl?-OH?was present on the surface of TiO₂ with a doping content of 1.0%of Fe³⁺,and the absorption band was red shifted,which was conducive to improve the photocatalytic performance of TiO₂.The optimal catalytic effect can be obtained by adjusting the initial pH of the reaction system and the initial concentration of RhB.In the reaction solution with pH=9,the RhB degradation rate of2.5mg/L was degraded by TiO₂ with a doping content of 1.0%at 83.97%,which was 16.32%higher than that of pure TiO₂ at 67.97%.TiO₂ doped with Cu²⁺was all anatase structure with better catalytic performance without rutile phase TiO₂,but excessive Cu²⁺will hinder the formation of anatase phase.Cu²⁺refined the grain size of TiO₂ and reduced its agglomeration.A large amount of hydroxyl?-OH?existed on the surface of TiO₂ with a doping content of 1.0%of Cu²⁺,which was conducive to improve the photocatalytic performance of TiO₂.The absorption spectra of TiO₂ was red shifted in different degrees.The best degradation rate of RhB by TiO₂ with a content of 1.0%was 87.65%,which was19.68%higher than that of pure TiO₂ with a content of 67.97%.The co-doping of Fe³⁺and Cu²⁺had better modification effect on TiO₂.The degradation rate of RhB by TiO₂ with doping content of 0.5%Cu²⁺and 0.5%Fe was 89.40%,and the degradation rate was improved by 21.75%.TiO₂ doped with Ce³⁺formed anatase phase,which was similar to Cu²⁺modification mechanism and did not form rutile phase.The addition of Ce³⁺refined the grain size of TiO₂ and improved the agglomeration.The doping of Ce³⁺made the surface of TiO₂ also had more hydroxyl.TiO₂ had red shifted in light absorption,and the absorption intensity in the ultraviolet region was obviously enhanced.The catalytic activity of TiO₂ was greatly enhanced by Ce³⁺doping.The best degradation rate of RhB by TiO₂ with Ce³⁺doping content of 1.0%was 85.79%,and it was18.14%higher than that by pure TiO₂.