Facile synthesis of hollow Co3O4 microspheres and its use as a rapid responsive CL sensor of combustible gases

The hollow Co3O4 microspheres (HCMs) were prepared by the carbonaceous templates, which did not need the surface pretreatment. The chemiluminescence (CL) and catalytic properties for CO oxidation over these hollow samples were evaluated. The samples were characterized by scanning electron microscopy (SEM), energy disperse spectra (EDS), transmission electron microscopy (TEM), selected area electron diffraction (ED), X-ray diffraction (XRD), temperature-programmed desorption (TPD) and N2 adsorption. The influences of filter’ band length, flow rate of gas, test temperature, and particle structure on CL intensities were mainly investigated. It was found that compared with the solid Co3O4 particles (SCPs), HCMs had a stronger CL intensity, which was ascribed to its hollow structure; and that CL properties of the catalysts were well correlated with their reaction activities. Moreover, HCMs were used to fabricate a highly sensitive gas detector, which is a rapid and effective method for the selection of catalysts or the detection of environmental deleterious gases.