| 초록 |
Conversion of CO2 into CO and hydrocarbon using solar irradiation has been intensively studued, yet it's efficiency and selectivity remains to be improved. In photocatalysis, CO2 adsorbed on the catalyst surface plays an important role in determining activity and selectivity because stabilized CO2 can react with adsorbed proton or hydroxyl groups without detachment. In this study, we carried out gas-phase conversion of CO2 using Cu/TiO2 nanoparticles as photocatalyst, showing significant enhancement when ligand is passivated on the surface. The reaction conditions are 0.4 mg of catalyst in DI water, 300 W Xe lamp, and 1 atm of CO2 gas at room temperature. Interestingly, CH4 production rate increased 4 times and CO production rate decreased when taurine is passivated on Cu/TiO2 photocatalyst. However, CO production rate increased when ethylenediamine treated. These results is proved by in-situ FT-IR under photocatalytic CO2 conversion condition. Also, DFT calculation shows surface ligand can control the selectivity of CO2 conversion by changing of CO binding strength. |
