Preparation of nano-TiO2 microspheres and photocatalytic degradation of gaseous benzene
The nano-TiO2 microspheres were prepared using TiCl4 and CON2H4 as raw materials by a simple sol-vothermal method.XRD,FESEM,TEM,UV-vis,BET methods were used to directly analyze the composi-tion,structure,morphology,optical properties and specific surface characteristics of the samples.The photo-catalytic activity of the microspheres prepared with different solvothermal time was determined by analyzing the degradation of gaseous benzene.The results show that the TiO2 microspheres have undergone a process of TiO2 solid-core,core-shell and hollow-center structure with the extension of reaction time,but they are all composed of particles below 20 nm.The light absorption band edge of the microspheres exhibits a significant"blue shift"phenomenon,the light absorption performance is higher than P25 TiO2,and the specific surface area is 3-5 times higher than that of P25 TiO2.The core-shell structure microspheres prepared by 6 h exhibit the highest photocatalytic activity,the mineralization rate of degraded gaseous benzene is as high as 93%,which is nearly three times higher than P25 TiO2.The excellent performance may ascribe to the sufficient reflection and absorp-tion of light by the core-shell structure,and the adsorption synergistic photocatalytic properties by the high spe-cific surface area.