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用溶胶 -凝胶法合成了 La1 - x Cex Fe1 - y - n Coy Run O3( x,y=0 .1～ 0 .5 ,n=0 .0 1～ 0 .1 )系列催化剂 ,XRD对晶体结构的表征发现 ,掺入 Ru后基本结构未改变 ,但 2 θ值减小 ,晶胞参数变大 .红外光谱分析表明 ,Ru改性的催化剂对应的特征峰位和峰形基本相似 ,但随着 Ru掺杂量的增加 ,60 0 cm- 1 附近的谱带向高波数方向移动 ,n=0 .0 1的样品 ,ν1 和 ν2 向低波数方向移动 ,n=0 .0 5样品的 ν1 带出现最大吸收峰 .XPS研究表明 ,掺杂 Ru后 Fe的外层电荷密度增大 ,并以多种价态存在 ;随着掺杂量的增加 ,表层中的 Ce由与氧结合转变为与多羟基结合 ,其它氧种含量增加 ,催化活性增强 .O2 -TPD结果表明 ,掺杂 Ru使催化剂表面的吸附氧和晶格氧脱附温度降低 ,A离子空位增加 .H2 -TPR研究表明 ,掺杂 Ru使 A离子空位增加 ,晶格氧活动性增强 ,催化活性提高 ;La0 .8Ce0 .2 Fe0 .7Co0 .2 Ru0 .1 O3的催化性能最佳 .
The La1 - xCexFe1 - y - n Coy Run O3 (x, y = 0.1-1.5, n = 0.001-0.1) catalysts were synthesized by sol - gel method. The results showed that the basic structure of Ru was not changed, but the value of 2θ was decreased and the unit cell parameters were increased. The infrared spectra showed that the corresponding peaks and peak shapes of Ru-modified catalysts were similar, With the increase of the amount of Ru doping, the band near 60 0 cm-1 shifts to the direction of higher wave number, the sample of n = 0. 01, ν1 and ν2 move towards the low wave number, n = 0. With the maximum absorption peak appears.XPS studies have shown that doped with Ru after the outer charge density increases, and exist in a variety of valence; with the doping amount increased, the surface of the Ce by the combination of oxygen into and Polyhydroxyl group, the content of other oxygen species increased, and the catalytic activity enhanced.O2 -TPD results show that doped Ru on the catalyst surface oxygen adsorption and lattice oxygen desorption temperature decreases, A ion vacancies increase.H2 -TPR studies have shown that the doped The heterogeneous Ru increases the vacancies of A ions and enhances the activity of lattice oxygen, and improves the catalytic activity. The catalytic activity of La0.8Ce0.2Fe0.7Co0.2 Ru0.1O3 is the best.