Heterostructured catalysts prepared by dispersing Au@Fe2O3 core–shell structures on supports and their performance in CO oxidation

Herein, we report novel gold catalysts made by dispersing Au@Fe2O3 core–shell structures on solid supports. In the synthesis of Au@Fe2O3 core–shell structures, dodecanethiol-capped gold nanoparticles were used as the seed and Fe(CO)5 was used as the precursor to Fe2O3 shell. The Au@Fe2O3 core–shell particles were deposited onto SiO2 support to obtain Au@Fe2O3/SiO2 catalysts that were highly active for low-temperature CO oxidation. The catalytic activity was even higher than that of Au/SiO2 or Au/Fe2O3 prepared by colloidal deposition with comparable gold loadings. The influences of thermal pretreatment, shell thickness, and different supports (e.g., SiO2, TiO2, C, Fe2O3) were investigated, and relevant characterization using TG/DTG, XRD, TEM, HAADF, and EDX was conducted.