Hierarchical structure based on Pd(Au) nanoparticles grafted onto magnetite cores and double layered shells: enhanced activity for catalytic applications

We report the creation of highly efficient sandwich-like structured nanocatalysts consisting of magnetic Fe3O4 cores, porous SiO2 and CeO2 shells and coated with noble metal nanoparticles (NMNPs). The nanocatalysts possess uniform sizes, variable shell compositions and thicknesses, adjustable noble metal nanoparticle coatings, tunable morphologies and good structural stability, and can be used as unique catalysts with extremely high catalytic activity and stability for the 4-nitrophenol reduction reaction due to their structural features with multiple interactions and strong synergistic effects between the noble metal nanoparticles and the cerium oxide shells. The designed double shelled Fe3O4@SiO2@CeO2/M nanocatalysts can be used as novel catalyst systems with highly efficient catalytic performance for various catalytic reactions depending on their shell components and noble nanoparticle coating. The synthetic strategy provides a new methodology to design high-performance and recyclable nanocatalysts.