Novel heterostructural Fe 2 O 3 CeO 2 /Au/carbon yolk – shell magnetic ellipsoids assembled with ultrafine Au nanoparticles for superior catalytic performance

Abstract

Abstract We report herein the successful design of novel Au-assembled heterostructural yolk-shell magentic ellipsoids (Fe2O3 CeO2/Au/H-mC) through a facile and rational synthetic strategy. These target products comprised magnetic Fe2O3 CeO2 spindles, mesoporous carbon shells and well-dispersed sub-2 nm Au nanoparticles. Firstly, double-layered SiO2/polymer resin composites were uniformly coated on Fe2O3 CeO2 spindles in a single step via the surfactant-free extended Stober route. Subsequent carbonization-hydrothermal etching was conducted for the formation of movable magnetic hybrid metal-oxide cores within mesoporous carbon hollow shells to achieve hierarchical Fe2O3 CeO2/carbon yolk-shell magnetic architectures. Finally, by inducing the low-temperature H2 reduction combined with the [Au(en)2]3+-mediated deposition-precipitation method, abundant ultrafine Au nanoparticles were in situ synthesized within these modulated ellipsoids, displaying incredible thermal stability and dispersibility due to the stabilization effect of capped ethylenediamine ligands. Impressively, taking advantages of unique heterostructural characteristics for strengthened composite synergies and electronic interactions, these Fe2O3 CeO2/Au/H-mC ellipsoids as powerful nanoreactors manifested the merits of superior catalytic performance, feasible recovery and excellent reusability for efficient reduction of 4-nitrophenol and organic dyes under mild conditions. The synthetic protocol can be instructive for the creation of other high-efficiency nanocatalysts with complex multifunctional architectures.