Hierarchical Fe3O4@Co3O4 core-shell microspheres: Preparation and acetone sensing properties

Hierarchical Fe3O4@Co3O4 core-shell microspheres were prepared through a simple two-step hydrothermal method. The structure, morphology and surface characteristics of the microspheres were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer-Emmett-Teller (BET). The results showed that porous architectures were assembled from Fe3O4 sphere core and Co3O4 flower-like shells. The gas sensing investigations revealed that the Fe3O4@Co3O4 core-shell microspheres sensors exhibited enhanced sensing properties to acetone compared with Fe3O4 microspheres and Co3O4 nanomaterials, which might be attributed to the unique hierarchical structure and the synergetic effect exerted by Fe3O4 and Co3O4.