空气辉光放电等离子体制备Pd/C催化剂及其催化Suzuki偶联反应

Air Glow Discharge Plasma Reduction to Synthesize Pd/C Catalyst for Suzuki Coupling Reaction

以活性炭为载体,通过空气辉光放电等离子体技术制备了负载型钯催化剂(Pd/C-P),并通过X射线衍射(XRD)、N_2物理吸附、透射电子显微镜(TEM)手段对制备的催化剂进行表征。结果表明,经等离子体还原15min制得的Pd/C-P-15催化剂的平均颗粒尺寸为23.3nm。而还原30min制备的催化剂有PdO生成。催化结果表明,以K_2CO_3为碱,EtOH/H_2O(1∶1)为溶剂,Pd/C-P-15催化剂用量为底物的0.5mmol‰,在60℃下催化对溴甲苯和苯硼酸的Suzuki偶联反应30min后,收率可达97%,且在循环使用3次后,收率降为85%。

The supported Pd catalyst（Pd/C-P）was synthesized by air glow discharge plasma technology with activated carbon as supporter. The Pd/C-P catalysts were characterized by X-ray diffraction（XRD）, N2 adsorption-desorption, and transmission electron microscope（TEM）. The results suggested that the Pd nanoparticles with an average particle size of 23.3nm were formed in Pd/C-P-15 by plasma reduction for 15min. The formation of PdO was found in Pd/C-P prepared by plasma reduction for 30min. A yield of 97% for the Suzuki coupling reaction between p-bromotoluene with phenylboronic acid was obtained which reacted for 30min in the presence of 0.5mmol‰ Pd/C-P-15 with EtOH/H2O （1：1）as solvent and K2CO3 as base. The Pd/C-P-15 could be recovered, but the yield dropped to 85% after the third recycle.