Cationic and macroporous amberlite resins with formate (HCOO−) as the counter anion (ARF) have been used to prepare a new class of heterogeneous Pd/Cu bimetallic composite nanoparticles (NPs) (Pd/Cu–ARF). The physicochemical characteristics of Pd/Cu–ARF were examined with the help of FTIR spectroscopy, X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and atomic absorption spectroscopy (AAS). XRD and TEM showed the existence of composite NPs made of metallic Pd, PdO and CuO. The TEM analysis revealed fairly uniform distributions of composite NPs of average size ∼4.9 nm. The as-synthesized nanocomposite material (Pd/Cu–ARF) exhibited high catalytic activity in the Sonogashira cross-coupling reaction between aryl iodide and terminal alkynes. Heterogeneity of the catalytic activity was evidenced from different tests (hot-filtration and catalyst-poisoning experiments) and the recycling ability of the catalyst was examined for five consecutive runs without any significant loss of activity.
                                    一种以
甲酸根离子(HCOO−)作为对离子的阳离子和大孔Amberlite
树脂(ARF)被用来制备新型的非均相Pd/Cu双
金属复合纳米粒子(NPs)(Pd/Cu–ARF)。利用傅里叶变换红外光谱(FTIR)、X射线粉末衍射(XRD)、透射电子显微镜(
TEM)和原子吸收光谱(
AAS)对Pd/Cu–ARF的物理
化学特性进行了检查。XRD和
TEM显示出由
金属Pd、PdO和CuO组成的复合纳米粒子。
TEM分析揭示出复合纳米粒子均匀分布,平均大小为约4.9纳米。合成的纳米复合材料(Pd/Cu–ARF)在芳基
碘化物与末端
炔烃之间的Sonogashira交叉偶联反应中表现出高催化活性。多种测试(热过滤和催化剂中毒实验)证明了催化活性的非均匀性,同时催化剂在连续五轮反应中没有明显活性损失,表明其重复使用能力良好。