Mohammad Reza Nabid, Yasamin Bide and Maryam Abuali
RSC Adv., 2014,4, 35844-35851
The fabrication of yolk/shell spheres consisting of a movable magnetic core and a chitosan-derived porous carbon shell, and plenty of tiny coppercoresilvershell nanoparticles confined within the porous shell, is reported. Fe3O4 nanoclusters were first synthesized through a solvothermal method and then SiO2 shell was coated on the Fe3O4 surface via a sol–gel process. Subsequently, chitosan was used to modify the surface of Fe3O4@SiO2. Then, selective etching of the middle SiO2 layer was accomplished to obtain the yolk/shell Fe3O4@chitosan composites. Material consisting of coppercoresilvershell nanoparticles immobilized on each yolk/shell Fe3O4@chitosan-derived carbon nanoparticle could be synthesized starting with coppercoresilvershell nanoparticle–yolk/shell Fe3O4@chitosan composite; this is possible due to the well-known strong affinity of chitosan for transition metals. The ensuing catalyst was employed for the epoxidation reaction in aqueous media at ambient temperature. The products were obtained in high yields with the use of low amounts of the catalyst.

©  تمامی حقوق متعلق به سازمان پژوهش‌های علمی و صنعتی ایران می باشد.