Ozone-modified TiO₂ WithDominant ?001? Facet For Photocatalytic Degradation Of Toluene

Toluene is the main component of indoor air pollutants,which is extremely harmful to human health.So the problem of purifying toluene needs to be solved.Photocatalytic oxidation is an ideal approach to mineralize the pollution into harmless CO2 and H2O at ambient temperature utilizing a semiconductor photocatalyst and UV or near UV light source.Among these photocatalysts,TiO2 has become the most widely used material due to its advantage of low price,sensitive photoactivation and high chemical stability.Therefore,the photocatalytic degradation of toluene by TiO2 is favored by researchers.TiO2 has many exposed crystal faces,and the(001)crystal faces exhibit higher activity in these different exposed crystal faces.However,the single TiO2 exhibits low catalytic activity during the degradation process,which restricts the practical application of the technology.In this paper,we first used ozone to modify the TiO2 of(001)dominant surface and studied the mechanism of degrading gaseous toluene.This paper is divided into four chapters:the first chapter is the introduction,the second chapter is the preparation and performance characterization of the catalyst,the third chapter is the result and discussion of the catalyst performance,the fourth chapter is the summary.The first chapter is the introduction,which mainly introduces the relevant background,mechanism knowledge and recent progress of the VOCs degradation by TiO2.First,the introduction introduces the sources of VOCs that are common in our lives,the harm of their existence to our bodies,and some common treatment methods.Secondly,the application of TiO2 in the photocatalytic degradation of organic pollutants is introduced.Third,the research progress of ozone in the field of degrading pollutants is summarized.Finally,the research objectives and contents of this paper are introduced.The second chapter is the experimental part.It mainly lists the experimental drugs and instruments that will be used in the experimental process,describes the synthesis method of the catalyst and the surface treatment method of ozone,and explains the characterization method and test principle of the catalyst.The third chapter is the results and discussion.The photocatalysts were characterized by XRD,TEM,HRTEM,SEM and other methods to identify the synthesized sample was(001)TiO2.Raman,UV-vis,XPS,EPR and other characterization methods were used to investigate the crystal surface exposure ratio,band gap,chemical environment,and the type and quantity of photoactive free radicals.The photocatalytic activity of degrading gas phase toluene was carried out by photocatalytic activity evaluation apparatus.The adsorption and degradation processes of the gas phase toluene on the surface of TiO2 and O3/TiO2 were studied by the in-situ DRIFTS research apparatus,revealing the effect of ozone-modified TiO2 on photocatalytic activity.The fourth chapter summarizes the conclusions of this paper and looks forward to further work in the future.