Synthesis of one-dimensional porous Co3O4 nanobelts and their ethanol gas sensing properties

In this paper, one-dimensional porous Co3O4 nanobelts were synthesized via a facile template-free hydrothermal method and subsequent the thermal decomposition. Their microstructures and morphologies were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and N2 adsorption–desorption techniques. The results indicate that the reaction parameters such as the molar ratio of Co(NO3)2·6H2O to C2H4N4, the amount of Co(NO3)2·6H2O, the hydrothermal temperature and time play crucial rules in controlling the microstructures and morphologies of the as-prepared cobalt precursors. A possible formation mechanism was proposed. Moreover, the obtained porous Co3O4 nanobelts exhibit ethanol gas sensing properties superior to the commercial Co3O4 powders at a working temperature of 200 °C, suggesting their potential applications as nanosensors.