Research On The Preparation,characterization And Catalysts Properties Of Bismuth Titanate Supported Catalyst

In order to solve the greenhouse effect caused by the massive emission of carbon dioxide,the research on the catalytic conversion of CO₂ into hydrocarbons in an efficient,green and economical manner has received extensive attention from researchers.Use the spontaneous polarization of materials to generate built-in electric field to promote semiconductor catalyst carrier separation may be an effective way to improve the catalytic conversion efficiency of CO₂.In this thesis,Bi₄Ti₃O₁₂?BTO?semiconductor with a layered perovskite structure was selected as the catalyst for CO₂catalytic conversion.The catalytic performance of Bi₄Ti₃O₁₂ and its supported composite catalyst was investigated by using its high spontaneous polarization performance and controlling its polarization characteristics in the condition of high pressure and high temperature catalytic reaction.?1?BTO with different morphologies was prepared by hydrothermal method and the effect of Na OH concentration on the morphology of bismuth titanate was investigated.The crystal structures and morphology of sample's were characterized by XRD,FT-IR,Raman and SEM.The optical absorption properties of sample's were tested by DRS.Bismuth titanate nanosheets were prepared when Na OH concentration was 3 mol/L,bismuth titanate nanosheets gradually crossed as the concentration increased,BTO hollow microspheres with rough surface were prepared when the Na OH concentration increased to 9 mol/L.The experiment of BTO catalytic conversion of CO₂was not detected the conversion product of CO₂,however,it has a high photocatalytic activity to degradate methyl orange.?2?Ag-BTO and BTO/g-C₃N₄ catalysts were prepared by loading Ag and compositing g-C₃N₄ on bismuth titanate nanosheets.The crystal structures and morphology of Ag-BTO and BTO/g-C₃N₄ were characterized by XRD,FT-IR,Raman and SEM.The optical absorption properties of Ag-BTO and BTO/g-C₃N₄ were tested by DRS.The load of Ag does not change the morphology of the BTO,but the absorption capacity of Ag-BTO for visible light is enhanced.Ag-BTO has not catalytic activity in the catalytic conversion of CO₂,however,it has high photocatalytic activity for methyl orange degradation.BTO/g-C₃N₄ composite catalyst has strong light absorption capacity,BTO/g-C₃N₄ has not catalytic activity in the catalytic conversion of CO₂,but it has high photocatalytic activity for methyl orange degradation.?3?The BTO/Ag/g-C₃N₄ catalyst was prepared by compositing Ag-BTO on g-C₃N₄,the crystal structure and morphology of BTO/Ag/g-C₃N₄ were characterized by XRD,FT-IR and SEM.The light absorption capacity of the catalyst was tested by DRS.The BTO/Ag/g-C₃N₄ catalyst exhibits a strong light absorbing ability.A little H₂ and CH₄was detected in the catalytic conversion of CO₂.