Preparation Of Titanium Dioxide Nanomaterials Modified By Noble Metals And Its Photocatalytic Properties

Water pollution is already a global concern,more and more areas because of water pollution caused by increased risk of neonatal morbidity,therefore,dealing with water pollution problems without delay.In the water pollution problem,the discharge of dye waste water,the pollution of heavy metal Cr ions,the discharge of medical waste liquid and so on are serious,which is a good method to settle issue for water contaminated,convenience and low cost photocatalyst.For a long time,the researchers for titanium dioxide photocatalysis is weak under visible light,photogenerated electrons and holes are overhead recovery rate of titanium dioxide photocatalyst modified.Based on TiO₂ optimization,mainly from the following aspects.First,based crystallinity of titanium dioxide enhanced,reduce the internal and grain boundary defects,improve the quantum efficiency of titanium dioxide,from the structure as much as possible to eliminate the defects of titanium dioxide.Second,based on titanium dioxide surface modification,the noble metal?or non?metallic surface modification.Third,based on the expansion of the specific surface area of titanium dioxide nanomaterials,increase the active sites of titanium dioxide and improve the utilization rate of titanium dioxide nanomaterials for photoelectrons.The main research work is as follows:?1?Gold-modified TiO₂nanofiberswerepreparedbyhigh-pressure electrospinning.The photocatalytic activity of gold modified titanium dioxide nanofibers was studied by changing the content of precursor gold and the simultaneous irradiation of ultraviolet and visible light.It was found that 0.075mol%Au modified TiO₂ nanofibers had the best photocatalytic activity,and discussed the transfer mechanism of electrons for photo-degradation of MB under ultraviolet and visible light irradiation.?2?Preparation of gold-modified carbon-doped TiO₂ nanotubes by high-voltage electrospinning.The gold-modified TiO₂-doped TiO₂ photocatalytic materials with narrow band gap and large specific surface area were obtained by changing the gold content of the precursor and the water-oil?W/O?phase separation.1 mol%Au-doped TiO₂ nanotubes had the best photocatalytic activity owing to it narrow bandgap for2.56 eV,large specific surface area of 76.9 m2/g,suitable plasma resonance band,etc.,2.5 times the catalyst of P25 by photo-degradation of RhB under visible light irradiation.At the same time,the photocatalytic activity of modified TiO₂ nanotubes with other different the content of Au were studied.?3?Preparation of silver modified TiO₂ nanoparticles exposed to crystal faces by hydrothermal method.The silver-modified TiO₂ photocatalytic materials were prepared by changing the silver content.2mol%Ag modified TiO₂ nanocubes had the best photocatalytic activity owing to narrow bandgap for 2.86 eV,which was 5 times of bare TiO₂ by photo-degradation of RhB under visible light irradiation.Meanwhile,a cause for low photocatalytic activity of other silver modified TiO₂ was studied,which is compared with 2mol%Ag modifed TiO₂ photocatalyst.