以金属有机骨架化合物ZIF-8为载体,Pd(C3H5)(C5H5)为金属有机前体,采用金属有机气相沉积方法在室温下制备了Pd@ZIF-8催化剂.Pd纳米粒子在ZIF-8载体上均匀分布,粒子尺寸约为1.5–3.5 nm.Pd@ZIF-8在温和条件下对多种卤代芳烃和苯硼酸的偶联反应均具有良好的活性.ZIF-8优异的化学稳定性不仅保证了其在制备过程中结构的完整,而且赋予了催化剂优异的循环使用性能.反应后Pd@ZIF-8材料的晶体结构、孔结构以及粒子分布均未发生明显的变化.
A zeolite-imidazolium-framework-supported Pd-based heterogeneous catalyst (Pd@ZIF-8) was prepared by a metal-organic chemical vapor deposition method under mild conditions using Pd(C3H5)(C5H5) as the Pd precursor. N2 adsorption and pore size distribution data showed that ZIF-8 and Pd@ZIF-8 both possessed high surface areas. Transmission electron microscopy images showed that Pd nanoparticles with sizes of about 1.5–3.5 nm were homogeneously dispersed on the ZIF-8 support in Pd@ZIF-8. The Pd@ZIF-8 catalyst showed good activity in Suzuki coupling reac-tions with several different kinds of aryl halides. It could be reused at least six times without dra-matic loss of activity or decomposition of the ZIF-8 structure.