Wang Zhe, Wan Haiqin, Liu Bin, Zhao Xi, Li Xiaowei, Zhu Haiyang, Xu Xuan, Ji Fangying, Sun Keqin, Dong Lin, Chen Yi
Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
J Colloid Interface Sci. 2008 Apr 15;320(2):520-6. doi: 10.1016/j.jcis.2008.02.001. Epub 2008 Feb 7.
XRD, BET, TPR, UV-vis DRS and in situ FT-IR were employed to investigate the dispersion, reduction and CO(2)-adsorption behaviors of copper oxide supported on magnesia modified gamma-Al(2)O(3) (Mg-Al) samples. The results indicate that magnesia could be highly dispersed on the surface of gamma-Al(2)O(3) to form a monolayer and the dispersion capacity is about 1.55 mmol/(100 m(2)gamma-Al(2)O(3)). For copper oxide supported on Mg-Al samples, both the dispersion capacity and the reduction temperature of surface CuO decrease with the MgO loading. CO(2)-adsorption IR results show that the surface strong basic amount for the catalysts increases with the dispersed MgO loading. In addition, the activity of CO oxidation suggests that the main active species in this system should be small CuO cluster and the existence of dispersed MgO enhances the activity of CO oxidation. The catalysts might be applied in pollution control devices for vehicle exhaust, CO gas sensors, catalytic combustion and gas purification of CO(2) lasers. All the results have been discussed by the consideration of the variation of gamma-Al(2)O(3) surface structure before and after magnesia modification.
采用X射线衍射（XRD）、比表面积测定（BET）、程序升温还原（TPR）、紫外可见漫反射光谱（UV-vis DRS）和原位傅里叶变换红外光谱（in situ FT-IR）研究了负载在氧化镁改性γ-氧化铝（Mg-Al）样品上的氧化铜的分散、还原及CO₂吸附行为。结果表明，氧化镁能够高度分散在γ-氧化铝表面形成单层，分散容量约为1.55 mmol/(100 m²γ-氧化铝)。对于负载在Mg-Al样品上的氧化铜，其分散容量和表面氧化铜的还原温度均随氧化镁负载量的增加而降低。CO₂吸附红外光谱结果表明，催化剂的表面强碱量随分散的氧化镁负载量增加而增加。此外，CO氧化活性表明该体系中的主要活性物种应为小的氧化铜簇，分散的氧化镁的存在增强了CO氧化活性。该催化剂可应用于车辆尾气污染控制装置、CO气体传感器、催化燃烧及CO₂激光器的气体净化。通过考虑氧化镁改性前后γ-氧化铝表面结构的变化对所有结果进行了讨论。
