Microporous tricobalt tetraoxide, Co3O4, nanoparticles (NPs) clusters have been successfully fabricated
using a simple but efficient controlled solution combustion route. Such a synthesis involves combustion
reaction of cobalt nitrate with cetyl trimethylammonium bromide (CTAB). The combustion process has
been analyzed by simultaneous thermal analysis. The resultant powders were characterized by means
of X-ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron
microscopy (SEM), Transmission electron microscopy (TEM) and nitrogen adsorption at 196 C. The
morphology and specific surface area of the obtained Co3O4 nanoparticles clusters have proved to be strongly dependent on the fuel (F)/oxidizer (O) molar ratio and the calcination temperature. It was found
that both the crystallite size and the lattice parameter nanocrystalline Co3O4 increase with increasing the F/O molar ratio as well as the calcination temperature. X-ray diffraction confirmed the formation of CoO phase together with spinel Co3O4 using F/O ratio of 1. The concentration of such phase increases with increasing the F/O ratio. Moreover, when the calcination is applied at 900–1000 C traces of CoO was obtained together with Co3O4 as a major phase.