Synthesis Of Ceria-Zirconium Solid Solutions With Template And Study On Oxygen Storage Capacity

A series of Ceria-Zirconium solid solutions were synthesized by the method of equality precipitation and different template self-assembly technology. After studied of the Ceria-Zirconium solid solutions, it was found that the parameters (reaction temperature and time, calcination temperature and time, concentration of reactant, the type and concentration of template, molar ratio of Ceria to Zirconium, etc) in the process of synthesis affected the specific surface area, crystal structure and oxygen storage capacity of the solid solutions. Three forms solid solutions of Ce-Zr-La, Ce-Zr-Y were synthesized on the same condition (CTAB as template, reacted 72hours at 80℃,urea as depositional reagent). Particularly analyzed affection parameters of the oxygen storage capacity and studied on its action theory after comparing the results of different forms of Ce,Ce-Zr,Ce-Zr-Y(La), different crystal structure of the same form and different specific surface area of the same crystal style. Tested the crystal, specific surface area and pore structure of Ceria-Zirconium solid solutions through the test method of XRD, BET and BJH. The results showed that the specific surface area was the largest(142m²/g) when the concentration of CTAB was 0.2mol/l; the crystal of Ceria-Zirconium solid solutions was stick nano-crystal when the reaction time was 72 hours; in the range of 24h⁷2h, the grain of solid solutions changed from stick to piece, and then switched back to stick; synthesized of solid solutions of different molar ratio of Ceria to Zirconium at 80℃and reacted 72hours, when the molar ratio of Ceria toZirconium was 1:9, the specific surface area was the largest(172m²/g). Studied on the oxygen storage capacity of CeO₂, Ce_xZr_1-xO₂, Ce-Zr-La, Ce-Zr-Y on 350℃through BET, SEM, TEM, OSC. It was found that the specific surface area and crystal structure of solid solutions affected OSC. The result indicated that the oxygen storage capacity of Ce_xZr_1-xO₂ was the best, and OSC of Ce-Zr-La(Y) was larger than CeO₂; when the molar ratio of Ceria to Zirconium was 5:5, 6:4, 7:3, OSC was large. So the parameters affected OSC were specific surface area, crystal structure...