Study On The Synthesis Of Strontium Titanate And Catalytic Conversion Of CO₂ Under High Temperature And High Pressure

In order to alleviate the energy and environmental problems,the researchers are paying more attention to the catalytic convert CO₂,such as photocatalytic,electric catalytic,thermal catalytic.But these catalytic methods exist many problems,such as harsh reaction conditions,low conversion rate,high energy input,and cann't large-scale applications,etc.It is expected that if those catalytic methods can be combined,and make the use of strata space environment of high temperature and high pressure forming a new way for large scale catalytic conversion of CO₂,this catalytic way would have great prospect and academic significance.This thesis selects SrTiO₃ as catalyst,which is widely used in photocatalytic,solar cells,and piezoelectric ceramic,using its semiconductor and spontaneous polarization characteristics.and explore the appropriate catalytic reaction conditions,try to use doping method changes the band structure of SrTiO₃ so that improve the catalytic performance.?1?SrTiO₃ are prepared by using sol-gel method,using XRD,SEM,DRS,Raman test sample's structure and morphology,using electrochemical method test the electrochemical activity.The high temperature and high pressure reaction kettle test is used to test its catalytic properties of CO₂ conversion under the condition of the dark state.The experimental results showed that the SrTiO₃ can only catalyze H₂O to H₂,but failed to convert CO₂ into hydrocarbon fuel at 150°C and 5 MPa.?2?To change energy band structure and the carrier concentration,the Li,Ag,and Ce of different atomic radii are doped into SrTiO₃.And then,electrochemical tests are used to analyze and compare the electrochemical performance of each catalyst under different solution environment,and the catalytic properties of the catalysts are studied by using high temperature and high pressure reactors to transform CO₂ under dark conditions.The result indicates that the doped SrTiO₃ shows poor electrochemical activity in saturated NaHCO₃ solution,and catalytic conversion product of CO₂ is not detected at 150°C and 5MPa.?3?In addition,the SrTiO₃ with strontium vacancy are synthesized and investigated the influence of strontium vacancy on piezoelectric polarization and reactivity.The microstructure and morphology are characterized by XRD,SEM,DRS and Raman et al.And the catalytic properties are studied by using high temperature and high pressure reactors to convert CO₂ under dark condition.The result shows that no catalytic conversion product of CO₂ is detected at 150°C and 5MPa.