A novel catalyst with a yolk-shell structure was designed to overcome the leaching of noble metals in heterogeneous catalysis. Through a template method, palladium (Pd) nanoparticles were encapsulated by hollow spherical covalent organic frameworks (COFs) consisting of 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (Tp) and p-phenylenediamine (Pa). The final catalyst with a yolk-shell structure was denoted as (Pd/C)@TpPa COFs. The unique morphology and chemical structure of this novel composite (Pd/C)@TpPa COFs were confirmed by a transmission electron microscope (TEM), a laser particle analyzer, X-ray diffraction (XRD), and N₂ adsorption and desorption. Subsequently, to demonstrate its catalytic performance brought by structural design, this novel catalyst was applied to catalyze the Suzuki reaction. Interestingly, this catalyst exhibited a brilliant size cutoff efficiency for aryl benzene amounting to 100% and achieved a high conversion with only 0.05 mol% Pd loading. Besides, this catalyst could be readily recovered via filtration and reused for at least five consecutive cycles without any significant loss in its activity.

设计了一种具有卵黄壳结构的新型催化剂，以克服多相催化中贵金属的浸出。通过模板方法，钯（Pd）纳米颗粒被空心球形共价有机骨架（COF）封装，该骨架由2,4,6-三羟基苯-1,3,5-三甲醛（Tp）和对苯二胺（Pa）组成。具有卵黄-壳结构的最终催化剂表示为（Pd / C）@TpPa COF。通过透射电子显微镜（TEM），激光粒子分析仪，X射线衍射（XRD）和N ₂证实了这种新型复合物（Pd / C）@TpPa COF的独特形态和化学结构。吸附和解吸。随后，为了证明其结构设计带来的催化性能，将该新型催化剂应用于催化Suzuki反应。有趣的是，该催化剂对芳基苯表现出极好的尺寸截留效率，总计为100％，并且仅以0.05 mol％的Pd负载实现了高转化率。此外，该催化剂可以很容易地通过过滤回收，并至少连续五个循环重复使用而活性没有明显损失。