Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption,XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Z...Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption,XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Zr0.5Ti0.5Al0.5O2 catalysts was evaluated using the simulated gases. The results show that ZTA samples exhibit higher specific surface area,larger pore volume and proper surface acidic amount and acidity in comparison with ZT. The results of the catalytic test indicate that Pt/ZT and Pt/ZTA catalysts exhibit excellent low-temperature catalytic activity and lower light-off temperatures of hydrocarbon,carbon monoxide and nitrogen oxides,especially better conversion for nitrogen oxides (NOx). The addition of Al2O3 into ZT enhanced the anti-aging property of Pt/ ZTA catalysts due to the excellent textural,structural,surface acidity and thermal stability.展开更多
Ce0.65Zr0.35O2 solid solution was prepared by co-precipitation method and characterized by X-ray diffraction (XRD), Raman spectra, BET, oxygen storage capacity (OSC) and temperature-programmed reduction measurements (...Ce0.65Zr0.35O2 solid solution was prepared by co-precipitation method and characterized by X-ray diffraction (XRD), Raman spectra, BET, oxygen storage capacity (OSC) and temperature-programmed reduction measurements (H2-TPR) after calcination at 100 ℃, 300 ℃, 600 ℃, and 1 000 ℃. The results showed that the precipitation was a crystalline of fluorite structure, and in the process of the precipitation transformation into Ce0.65Zr0.35O2 solid solution, the fluorite structure of the precipitation kept unchanged. The samples had different BET surface areas and OSC at different temperatures, but they held the performance of stable structure. After 1 000 ℃, there didn′t appear the other crystalline phase. So the samples prepared by co-precipitation method had excellent texture and higher thermal stability.展开更多
文摘Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption,XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Zr0.5Ti0.5Al0.5O2 catalysts was evaluated using the simulated gases. The results show that ZTA samples exhibit higher specific surface area,larger pore volume and proper surface acidic amount and acidity in comparison with ZT. The results of the catalytic test indicate that Pt/ZT and Pt/ZTA catalysts exhibit excellent low-temperature catalytic activity and lower light-off temperatures of hydrocarbon,carbon monoxide and nitrogen oxides,especially better conversion for nitrogen oxides (NOx). The addition of Al2O3 into ZT enhanced the anti-aging property of Pt/ ZTA catalysts due to the excellent textural,structural,surface acidity and thermal stability.
文摘Ce0.65Zr0.35O2 solid solution was prepared by co-precipitation method and characterized by X-ray diffraction (XRD), Raman spectra, BET, oxygen storage capacity (OSC) and temperature-programmed reduction measurements (H2-TPR) after calcination at 100 ℃, 300 ℃, 600 ℃, and 1 000 ℃. The results showed that the precipitation was a crystalline of fluorite structure, and in the process of the precipitation transformation into Ce0.65Zr0.35O2 solid solution, the fluorite structure of the precipitation kept unchanged. The samples had different BET surface areas and OSC at different temperatures, but they held the performance of stable structure. After 1 000 ℃, there didn′t appear the other crystalline phase. So the samples prepared by co-precipitation method had excellent texture and higher thermal stability.