论文部分内容阅读
The catalytic behaviors of Pd (1.4 wt%) catalysts supported on CeO2-ZrO2-La2O3 mixed oxides with different Ce/Zr molar ratios were investigated for methanol decomposition. Nitrogen adsorption-desorption (BET), X-ray photoelectron spectroscopy (XPS), H2 temperature-programmed reduction (H2-TPR), X-ray diffraction (XRD) and Pd dispersion analysis were used for their characterization. Pd/Ce0.76Zr0.18 La0.06O1.97 catalyst showed the highest BET surface area, best Pd dispersion capability and strongest metal-support interaction. Moreover, XPS showed that there was lattice defect oxygen or mobile oxygen. According to the result of O 1s measurements the lattice defect oxygen or mobile oxygen helped to maintain Pd in a partly oxidized state and increased the activity for methanol decomposition. The Pd/Ce0.76Zr0.18La0.06O1.97 catalyst exhibited the best activity. A 100% conversion of methanol was achieved at around 260℃, which was about 20-40℃ lower than other catalysts
The catalytic behaviors of Pd (1.4 wt%) catalysts supported on CeO2-ZrO2-La2O3 mixed oxides with different Ce / Zr molar ratios were investigated for methanol decomposition. Nitrogen adsorption-desorption (BET), X-ray photoelectron spectroscopy Pd / Ce0.76Zr0.18 La0.06O1.97 catalyst showed the highest BET surface area, best Pd (H2-TPR), X-ray diffraction (XRD) and Pd dispersion analysis were used for their characterization XPS showed that there was lattice defect oxygen or mobile oxygen. According to the result of O 1s measurements the lattice defect oxygen or mobile oxygen helped to maintain Pd in a partly oxidized state and increased the Activity for methanol decomposition. The Pd / Ce 0.76Zr 0.18La 0.06O 1.97 catalyst exhibited the best activity. A 100% conversion of methanol was achieved at around 260 ° C, which was about 20-40 ° C lower than other catalysts