Pd nanoparticles in hollow magnetic mesoporous spheres: High activity, and magnetic recyclability

The nanoreactor of hollow magnetic mesoporous silica spheres (Pd/HMMS), with Pd and Fe3O4 nanoparticles embedded in the mesoporous silica shell, were successfully prepared by using the colloidal carbon spheres of glucose, Pd and Fe3O4 heteroaggregates as the hard template together with a coating of tetraethoxysilane (TEOS) and cetyltrimethylammonium bromide (CTAB) mixture. The synthesized Pd/HMMS shows excellent catalytic activity in the Suzuki cross-coupling reaction of iodobenzene with phenylboronic acid with over 99% yield in 3 min and can be recycled multiple times without any significant loss in catalytic activity.

Figure optionsDownload high-quality image (162 K)Download as PowerPoint slideHighlights
► The synthesized Pd/HMMS shows excellent catalytic activity in Suzuki cross-coupling reaction with over 99% yield in 3 min and can be recycled multiple times without any significant loss in catalytic activity.
► Facile mass transfer is possible as the Pd nanoparticles are well-dispersed inside the mesoporous silica shell without aggregation.
► The catalyst was easily recovered from the reaction mixture with external magnetic field.
► The Pd/HMMS structure can be extended to introduce other noble metal nanoparticles.