聚芳醚三乙酸铵树枝分子保护的Pt、Pd纳米粒子的制备及催化性能

Preparation and Catalysis of Platinum and Palladium Nanoparticles Capped with Polyaryl Ether Trisacetic Acid Ammonium Chloride Dendrimer

以聚芳醚三乙酸氯化铵树枝分子为稳定剂在乙醇水溶液中制备了金属Pt和Pd纳米粒子。通过UV-Vis、IR、TEM和XRD等方法对纳米粒子进行了表征。聚芳醚三乙酸氯化铵树枝分子根部3个乙酸基基团与金属纳米粒子表面原子间具有较强的相互作用,以其为稳定剂制备的Pt和Pd金属纳米粒子在溶胶中及反应过程中均表现出很好的稳定性。以间苯氧基苯甲醛催化加氢反应为模型反应,研究了Pt和Pd金属纳米粒子的催化反应性能。以Pt金属纳米粒子为催化剂,在常压,40℃下反应12h,间苯氧基苯甲醛加氢转化率大于99%,在相同反应条件下Pt金属纳米粒子的催化加氢活性高于Pd金属纳米粒子。

Nanoparticles of platinum and palladium capped with polyaryl ether trisacetic acid ammonium chloride dendrimer in generation three （Pt-G3-NA and Pd-G3-NA） were prepared by an ethanol reduction method and characterized with UV-Vis, IR, TEM and XRD. The metal nanoparticles obtained are stable both in colloidal solution and in catalytic hydrogenation process since the relative strong interaction among the surface atoms of the nanoparticle and the acetic acid groups of the dendrimer. The catalytic activities of Pt and Pd dendrimer-metal nanoparticles were tested by the hydrogenation of m-phenoxy benzaldehyde. Under an atmospheric pressure of H2, the conversion of m-phenoxy benzaldehyde was beyond 99 % after 12 h of reaction at 40 ℃. The activity of catalytic hydrogenation of Pt-Gn-NA was higher than that of Pd-G3-NA at the same reaction conditions.