| With the improvement of quality of life,there are higher requirements for the environment of living cities and places.The methods for solving pollution problems include physical methods and chemical methods.Physical methods mainly involve adsorption of pollutants,and chemical methods are through the degradation of pollutants.In chemical methods,it is especially important to find a non-toxic,low-cost catalyst.TiO2 is a catalyst that meets these two requirements.In this paper,in order to solve the problems of TiO2 in the current research,different TiO2 films were prepared on the substrate of quartz capillary and glass sheet.In the first part,we prepared a Fe3+doped TiO2 capillary monolithic column.The tetra-n-butyl titanate was used as the titanium source,and the ferric nitrate nonahydrate was used as the Fe3+doping source.The Fe3+-TiO2 film was loaded on the inner wall of the capillary by sol-gel method.The surface morphology of the film and the actual doping ratio of the film were tested by SEM and EDS.The crystal structure of the film was tested by XRD,and the nanoparticle size was calculated by Debye-Scherrer formula.The absorption properties of ultraviolet light and visible light was tested by UV-Vis.In the second part,we used butyl titanate as the titanium source,polystyrene as the template,chloroform as the organic solvent respectively,then a layer of porous TiO2 film was prepared on the glass sheet.The films prepared in different reaction times were tested by SEM,the formation of porous films was studied by combining TGA and FTIR results.Methylene blue was used as a degradant of the two types of films to study the best catalytic properties among them.(1)A layer of Fe3+-TiO2 film is loaded on the inner wall of the capillary by sol-gel method.The EDS results show that the actual doping ratio is lower than the raw material ratio.As the doping ratio increases,the crystal form of TiO2 does not change,the crystallinity and nanopaticle size decrease,and the flatness of the film increases.The degradation of 8.5%Fe3+-TiO2 film was the best,and the degradation rate was 96%.(2)A layer of porous TiO2 film grown on a glass sheet substrate by breath figures method and a further reaction.The size of polystyrene microspheres is about 1 micrometre,the water vapor reaction time is longer than 10 hours,the mass ratio of polystyrene to tetra-n-butyl titanate is less than 1:1.5,and the calcination temperature is higher than 500?.UV-Vis results showed the highest absorption at 500?,followed by 400? and 600?.We studied the formation of thin films and concluded as follows:the organic solvent absorbed heat and evaporated in a humid atmosphere,then the TBOT hydrolyzed and a TiO2 film having a diameter of 10?m was formed on the surface;The film continued to react in water vapor to hydrolyze TBOT completely,and the porous film having a pore diameter of 10 ?m disappeared gradually;The film was calcined in a muffle furnace,the polystyrene became flowing polystyrene when the temperature exceeds its glass transition temperature,and continued to infiltrate into the TiO2 film,then a porous TiO2 film was obtained after the polystyrene was removed completely by calcination.The methylene blue was degraded by using a porous TiO2 film prepared under different conditions,the best porous TiO2 film degradation rate was 94%. |
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